The first part of the Project: data primary reading

This is an R Markdown document. It is made in Knitr package

# url1 = "https://d396qusza40orc.cloudfront.net/predmachlearn/pml-training.csv"
# url2 = "https://d396qusza40orc.cloudfront.net/predmachlearn/pml-testing.csv"
# Too long to download from URL directly
url1 = "C:/Users/Alex/Documents/COURSERA STUDIES/Practical Machine Learning/Final_Project/pml-training.csv"
url2 = "C:/Users/Alex/Documents/COURSERA STUDIES/Practical Machine Learning/Final_Project/pml-testing.csv"

training = read.csv(paste0(url1),na.strings=c("NA","#DIV/0!",""))
testing = read.csv(paste0(url2),na.strings=c("NA","#DIV/0!",""))
dim(training)
## [1] 19622   160
dim(testing)
## [1]  20 160
summary(training)
##        X          user_name         raw_timestamp_part_1 raw_timestamp_part_2
##  Min.   :    1   Length:19622       Min.   :1.322e+09    Min.   :   294      
##  1st Qu.: 4906   Class :character   1st Qu.:1.323e+09    1st Qu.:252912      
##  Median : 9812   Mode  :character   Median :1.323e+09    Median :496380      
##  Mean   : 9812                      Mean   :1.323e+09    Mean   :500656      
##  3rd Qu.:14717                      3rd Qu.:1.323e+09    3rd Qu.:751891      
##  Max.   :19622                      Max.   :1.323e+09    Max.   :998801      
##                                                                              
##  cvtd_timestamp      new_window          num_window      roll_belt     
##  Length:19622       Length:19622       Min.   :  1.0   Min.   :-28.90  
##  Class :character   Class :character   1st Qu.:222.0   1st Qu.:  1.10  
##  Mode  :character   Mode  :character   Median :424.0   Median :113.00  
##                                        Mean   :430.6   Mean   : 64.41  
##                                        3rd Qu.:644.0   3rd Qu.:123.00  
##                                        Max.   :864.0   Max.   :162.00  
##                                                                        
##    pitch_belt          yaw_belt       total_accel_belt kurtosis_roll_belt
##  Min.   :-55.8000   Min.   :-180.00   Min.   : 0.00    Min.   :-2.121    
##  1st Qu.:  1.7600   1st Qu.: -88.30   1st Qu.: 3.00    1st Qu.:-1.329    
##  Median :  5.2800   Median : -13.00   Median :17.00    Median :-0.899    
##  Mean   :  0.3053   Mean   : -11.21   Mean   :11.31    Mean   :-0.220    
##  3rd Qu.: 14.9000   3rd Qu.:  12.90   3rd Qu.:18.00    3rd Qu.:-0.219    
##  Max.   : 60.3000   Max.   : 179.00   Max.   :29.00    Max.   :33.000    
##                                                        NA's   :19226     
##  kurtosis_picth_belt kurtosis_yaw_belt skewness_roll_belt skewness_roll_belt.1
##  Min.   :-2.190      Mode:logical      Min.   :-5.745     Min.   :-7.616      
##  1st Qu.:-1.107      NA's:19622        1st Qu.:-0.444     1st Qu.:-1.114      
##  Median :-0.151                        Median : 0.000     Median :-0.068      
##  Mean   : 4.334                        Mean   :-0.026     Mean   :-0.296      
##  3rd Qu.: 3.178                        3rd Qu.: 0.417     3rd Qu.: 0.661      
##  Max.   :58.000                        Max.   : 3.595     Max.   : 7.348      
##  NA's   :19248                         NA's   :19225      NA's   :19248       
##  skewness_yaw_belt max_roll_belt     max_picth_belt   max_yaw_belt  
##  Mode:logical      Min.   :-94.300   Min.   : 3.00   Min.   :-2.10  
##  NA's:19622        1st Qu.:-88.000   1st Qu.: 5.00   1st Qu.:-1.30  
##                    Median : -5.100   Median :18.00   Median :-0.90  
##                    Mean   : -6.667   Mean   :12.92   Mean   :-0.22  
##                    3rd Qu.: 18.500   3rd Qu.:19.00   3rd Qu.:-0.20  
##                    Max.   :180.000   Max.   :30.00   Max.   :33.00  
##                    NA's   :19216     NA's   :19216   NA's   :19226  
##  min_roll_belt     min_pitch_belt   min_yaw_belt   amplitude_roll_belt
##  Min.   :-180.00   Min.   : 0.00   Min.   :-2.10   Min.   :  0.000    
##  1st Qu.: -88.40   1st Qu.: 3.00   1st Qu.:-1.30   1st Qu.:  0.300    
##  Median :  -7.85   Median :16.00   Median :-0.90   Median :  1.000    
##  Mean   : -10.44   Mean   :10.76   Mean   :-0.22   Mean   :  3.769    
##  3rd Qu.:   9.05   3rd Qu.:17.00   3rd Qu.:-0.20   3rd Qu.:  2.082    
##  Max.   : 173.00   Max.   :23.00   Max.   :33.00   Max.   :360.000    
##  NA's   :19216     NA's   :19216   NA's   :19226   NA's   :19216      
##  amplitude_pitch_belt amplitude_yaw_belt var_total_accel_belt avg_roll_belt   
##  Min.   : 0.000       Min.   :0          Min.   : 0.000       Min.   :-27.40  
##  1st Qu.: 1.000       1st Qu.:0          1st Qu.: 0.100       1st Qu.:  1.10  
##  Median : 1.000       Median :0          Median : 0.200       Median :116.35  
##  Mean   : 2.167       Mean   :0          Mean   : 0.926       Mean   : 68.06  
##  3rd Qu.: 2.000       3rd Qu.:0          3rd Qu.: 0.300       3rd Qu.:123.38  
##  Max.   :12.000       Max.   :0          Max.   :16.500       Max.   :157.40  
##  NA's   :19216        NA's   :19226      NA's   :19216        NA's   :19216   
##  stddev_roll_belt var_roll_belt     avg_pitch_belt    stddev_pitch_belt
##  Min.   : 0.000   Min.   :  0.000   Min.   :-51.400   Min.   :0.000    
##  1st Qu.: 0.200   1st Qu.:  0.000   1st Qu.:  2.025   1st Qu.:0.200    
##  Median : 0.400   Median :  0.100   Median :  5.200   Median :0.400    
##  Mean   : 1.337   Mean   :  7.699   Mean   :  0.520   Mean   :0.603    
##  3rd Qu.: 0.700   3rd Qu.:  0.500   3rd Qu.: 15.775   3rd Qu.:0.700    
##  Max.   :14.200   Max.   :200.700   Max.   : 59.700   Max.   :4.000    
##  NA's   :19216    NA's   :19216     NA's   :19216     NA's   :19216    
##  var_pitch_belt    avg_yaw_belt      stddev_yaw_belt    var_yaw_belt      
##  Min.   : 0.000   Min.   :-138.300   Min.   :  0.000   Min.   :    0.000  
##  1st Qu.: 0.000   1st Qu.: -88.175   1st Qu.:  0.100   1st Qu.:    0.010  
##  Median : 0.100   Median :  -6.550   Median :  0.300   Median :    0.090  
##  Mean   : 0.766   Mean   :  -8.831   Mean   :  1.341   Mean   :  107.487  
##  3rd Qu.: 0.500   3rd Qu.:  14.125   3rd Qu.:  0.700   3rd Qu.:    0.475  
##  Max.   :16.200   Max.   : 173.500   Max.   :176.600   Max.   :31183.240  
##  NA's   :19216    NA's   :19216      NA's   :19216     NA's   :19216      
##   gyros_belt_x        gyros_belt_y       gyros_belt_z      accel_belt_x     
##  Min.   :-1.040000   Min.   :-0.64000   Min.   :-1.4600   Min.   :-120.000  
##  1st Qu.:-0.030000   1st Qu.: 0.00000   1st Qu.:-0.2000   1st Qu.: -21.000  
##  Median : 0.030000   Median : 0.02000   Median :-0.1000   Median : -15.000  
##  Mean   :-0.005592   Mean   : 0.03959   Mean   :-0.1305   Mean   :  -5.595  
##  3rd Qu.: 0.110000   3rd Qu.: 0.11000   3rd Qu.:-0.0200   3rd Qu.:  -5.000  
##  Max.   : 2.220000   Max.   : 0.64000   Max.   : 1.6200   Max.   :  85.000  
##                                                                             
##   accel_belt_y     accel_belt_z     magnet_belt_x   magnet_belt_y  
##  Min.   :-69.00   Min.   :-275.00   Min.   :-52.0   Min.   :354.0  
##  1st Qu.:  3.00   1st Qu.:-162.00   1st Qu.:  9.0   1st Qu.:581.0  
##  Median : 35.00   Median :-152.00   Median : 35.0   Median :601.0  
##  Mean   : 30.15   Mean   : -72.59   Mean   : 55.6   Mean   :593.7  
##  3rd Qu.: 61.00   3rd Qu.:  27.00   3rd Qu.: 59.0   3rd Qu.:610.0  
##  Max.   :164.00   Max.   : 105.00   Max.   :485.0   Max.   :673.0  
##                                                                    
##  magnet_belt_z       roll_arm         pitch_arm          yaw_arm         
##  Min.   :-623.0   Min.   :-180.00   Min.   :-88.800   Min.   :-180.0000  
##  1st Qu.:-375.0   1st Qu.: -31.77   1st Qu.:-25.900   1st Qu.: -43.1000  
##  Median :-320.0   Median :   0.00   Median :  0.000   Median :   0.0000  
##  Mean   :-345.5   Mean   :  17.83   Mean   : -4.612   Mean   :  -0.6188  
##  3rd Qu.:-306.0   3rd Qu.:  77.30   3rd Qu.: 11.200   3rd Qu.:  45.8750  
##  Max.   : 293.0   Max.   : 180.00   Max.   : 88.500   Max.   : 180.0000  
##                                                                          
##  total_accel_arm var_accel_arm     avg_roll_arm     stddev_roll_arm  
##  Min.   : 1.00   Min.   :  0.00   Min.   :-166.67   Min.   :  0.000  
##  1st Qu.:17.00   1st Qu.:  9.03   1st Qu.: -38.37   1st Qu.:  1.376  
##  Median :27.00   Median : 40.61   Median :   0.00   Median :  5.702  
##  Mean   :25.51   Mean   : 53.23   Mean   :  12.68   Mean   : 11.201  
##  3rd Qu.:33.00   3rd Qu.: 75.62   3rd Qu.:  76.33   3rd Qu.: 14.921  
##  Max.   :66.00   Max.   :331.70   Max.   : 163.33   Max.   :161.964  
##                  NA's   :19216    NA's   :19216     NA's   :19216    
##   var_roll_arm       avg_pitch_arm     stddev_pitch_arm var_pitch_arm     
##  Min.   :    0.000   Min.   :-81.773   Min.   : 0.000   Min.   :   0.000  
##  1st Qu.:    1.898   1st Qu.:-22.770   1st Qu.: 1.642   1st Qu.:   2.697  
##  Median :   32.517   Median :  0.000   Median : 8.133   Median :  66.146  
##  Mean   :  417.264   Mean   : -4.901   Mean   :10.383   Mean   : 195.864  
##  3rd Qu.:  222.647   3rd Qu.:  8.277   3rd Qu.:16.327   3rd Qu.: 266.576  
##  Max.   :26232.208   Max.   : 75.659   Max.   :43.412   Max.   :1884.565  
##  NA's   :19216       NA's   :19216     NA's   :19216    NA's   :19216     
##   avg_yaw_arm       stddev_yaw_arm     var_yaw_arm         gyros_arm_x      
##  Min.   :-173.440   Min.   :  0.000   Min.   :    0.000   Min.   :-6.37000  
##  1st Qu.: -29.198   1st Qu.:  2.577   1st Qu.:    6.642   1st Qu.:-1.33000  
##  Median :   0.000   Median : 16.682   Median :  278.309   Median : 0.08000  
##  Mean   :   2.359   Mean   : 22.270   Mean   : 1055.933   Mean   : 0.04277  
##  3rd Qu.:  38.185   3rd Qu.: 35.984   3rd Qu.: 1294.850   3rd Qu.: 1.57000  
##  Max.   : 152.000   Max.   :177.044   Max.   :31344.568   Max.   : 4.87000  
##  NA's   :19216      NA's   :19216     NA's   :19216                         
##   gyros_arm_y       gyros_arm_z       accel_arm_x       accel_arm_y    
##  Min.   :-3.4400   Min.   :-2.3300   Min.   :-404.00   Min.   :-318.0  
##  1st Qu.:-0.8000   1st Qu.:-0.0700   1st Qu.:-242.00   1st Qu.: -54.0  
##  Median :-0.2400   Median : 0.2300   Median : -44.00   Median :  14.0  
##  Mean   :-0.2571   Mean   : 0.2695   Mean   : -60.24   Mean   :  32.6  
##  3rd Qu.: 0.1400   3rd Qu.: 0.7200   3rd Qu.:  84.00   3rd Qu.: 139.0  
##  Max.   : 2.8400   Max.   : 3.0200   Max.   : 437.00   Max.   : 308.0  
##                                                                        
##   accel_arm_z       magnet_arm_x     magnet_arm_y     magnet_arm_z   
##  Min.   :-636.00   Min.   :-584.0   Min.   :-392.0   Min.   :-597.0  
##  1st Qu.:-143.00   1st Qu.:-300.0   1st Qu.:  -9.0   1st Qu.: 131.2  
##  Median : -47.00   Median : 289.0   Median : 202.0   Median : 444.0  
##  Mean   : -71.25   Mean   : 191.7   Mean   : 156.6   Mean   : 306.5  
##  3rd Qu.:  23.00   3rd Qu.: 637.0   3rd Qu.: 323.0   3rd Qu.: 545.0  
##  Max.   : 292.00   Max.   : 782.0   Max.   : 583.0   Max.   : 694.0  
##                                                                      
##  kurtosis_roll_arm kurtosis_picth_arm kurtosis_yaw_arm skewness_roll_arm
##  Min.   :-1.809    Min.   :-2.084     Min.   :-2.103   Min.   :-2.541   
##  1st Qu.:-1.345    1st Qu.:-1.280     1st Qu.:-1.220   1st Qu.:-0.561   
##  Median :-0.894    Median :-1.010     Median :-0.733   Median : 0.040   
##  Mean   :-0.366    Mean   :-0.542     Mean   : 0.406   Mean   : 0.068   
##  3rd Qu.:-0.038    3rd Qu.:-0.379     3rd Qu.: 0.115   3rd Qu.: 0.671   
##  Max.   :21.456    Max.   :19.751     Max.   :56.000   Max.   : 4.394   
##  NA's   :19294     NA's   :19296      NA's   :19227    NA's   :19293    
##  skewness_pitch_arm skewness_yaw_arm  max_roll_arm     max_picth_arm     
##  Min.   :-4.565     Min.   :-6.708   Min.   :-73.100   Min.   :-173.000  
##  1st Qu.:-0.618     1st Qu.:-0.743   1st Qu.: -0.175   1st Qu.:  -1.975  
##  Median :-0.035     Median :-0.133   Median :  4.950   Median :  23.250  
##  Mean   :-0.065     Mean   :-0.229   Mean   : 11.236   Mean   :  35.751  
##  3rd Qu.: 0.454     3rd Qu.: 0.344   3rd Qu.: 26.775   3rd Qu.:  95.975  
##  Max.   : 3.043     Max.   : 7.483   Max.   : 85.500   Max.   : 180.000  
##  NA's   :19296      NA's   :19227    NA's   :19216     NA's   :19216     
##   max_yaw_arm     min_roll_arm    min_pitch_arm      min_yaw_arm   
##  Min.   : 4.00   Min.   :-89.10   Min.   :-180.00   Min.   : 1.00  
##  1st Qu.:29.00   1st Qu.:-41.98   1st Qu.: -72.62   1st Qu.: 8.00  
##  Median :34.00   Median :-22.45   Median : -33.85   Median :13.00  
##  Mean   :35.46   Mean   :-21.22   Mean   : -33.92   Mean   :14.66  
##  3rd Qu.:41.00   3rd Qu.:  0.00   3rd Qu.:   0.00   3rd Qu.:19.00  
##  Max.   :65.00   Max.   : 66.40   Max.   : 152.00   Max.   :38.00  
##  NA's   :19216   NA's   :19216    NA's   :19216     NA's   :19216  
##  amplitude_roll_arm amplitude_pitch_arm amplitude_yaw_arm roll_dumbbell    
##  Min.   :  0.000    Min.   :  0.000     Min.   : 0.00     Min.   :-153.71  
##  1st Qu.:  5.425    1st Qu.:  9.925     1st Qu.:13.00     1st Qu.: -18.49  
##  Median : 28.450    Median : 54.900     Median :22.00     Median :  48.17  
##  Mean   : 32.452    Mean   : 69.677     Mean   :20.79     Mean   :  23.84  
##  3rd Qu.: 50.960    3rd Qu.:115.175     3rd Qu.:28.75     3rd Qu.:  67.61  
##  Max.   :119.500    Max.   :360.000     Max.   :52.00     Max.   : 153.55  
##  NA's   :19216      NA's   :19216       NA's   :19216                      
##  pitch_dumbbell     yaw_dumbbell      kurtosis_roll_dumbbell
##  Min.   :-149.59   Min.   :-150.871   Min.   :-2.174        
##  1st Qu.: -40.89   1st Qu.: -77.644   1st Qu.:-0.682        
##  Median : -20.96   Median :  -3.324   Median :-0.033        
##  Mean   : -10.78   Mean   :   1.674   Mean   : 0.452        
##  3rd Qu.:  17.50   3rd Qu.:  79.643   3rd Qu.: 0.940        
##  Max.   : 149.40   Max.   : 154.952   Max.   :54.998        
##                                       NA's   :19221         
##  kurtosis_picth_dumbbell kurtosis_yaw_dumbbell skewness_roll_dumbbell
##  Min.   :-2.200          Mode:logical          Min.   :-7.384        
##  1st Qu.:-0.721          NA's:19622            1st Qu.:-0.581        
##  Median :-0.133                                Median :-0.076        
##  Mean   : 0.286                                Mean   :-0.115        
##  3rd Qu.: 0.584                                3rd Qu.: 0.400        
##  Max.   :55.628                                Max.   : 1.958        
##  NA's   :19218                                 NA's   :19220         
##  skewness_pitch_dumbbell skewness_yaw_dumbbell max_roll_dumbbell
##  Min.   :-7.447          Mode:logical          Min.   :-70.10   
##  1st Qu.:-0.525          NA's:19622            1st Qu.:-27.15   
##  Median :-0.091                                Median : 14.85   
##  Mean   :-0.035                                Mean   : 13.76   
##  3rd Qu.: 0.505                                3rd Qu.: 50.58   
##  Max.   : 3.769                                Max.   :137.00   
##  NA's   :19217                                 NA's   :19216    
##  max_picth_dumbbell max_yaw_dumbbell min_roll_dumbbell min_pitch_dumbbell
##  Min.   :-112.90    Min.   :-2.20    Min.   :-149.60   Min.   :-147.00   
##  1st Qu.: -66.70    1st Qu.:-0.70    1st Qu.: -59.67   1st Qu.: -91.80   
##  Median :  40.05    Median : 0.00    Median : -43.55   Median : -66.15   
##  Mean   :  32.75    Mean   : 0.45    Mean   : -41.24   Mean   : -33.18   
##  3rd Qu.: 133.22    3rd Qu.: 0.90    3rd Qu.: -25.20   3rd Qu.:  21.20   
##  Max.   : 155.00    Max.   :55.00    Max.   :  73.20   Max.   : 120.90   
##  NA's   :19216      NA's   :19221    NA's   :19216     NA's   :19216     
##  min_yaw_dumbbell amplitude_roll_dumbbell amplitude_pitch_dumbbell
##  Min.   :-2.20    Min.   :  0.00          Min.   :  0.00          
##  1st Qu.:-0.70    1st Qu.: 14.97          1st Qu.: 17.06          
##  Median : 0.00    Median : 35.05          Median : 41.73          
##  Mean   : 0.45    Mean   : 55.00          Mean   : 65.93          
##  3rd Qu.: 0.90    3rd Qu.: 81.04          3rd Qu.: 99.55          
##  Max.   :55.00    Max.   :256.48          Max.   :273.59          
##  NA's   :19221    NA's   :19216           NA's   :19216           
##  amplitude_yaw_dumbbell total_accel_dumbbell var_accel_dumbbell
##  Min.   :0              Min.   : 0.00        Min.   :  0.000   
##  1st Qu.:0              1st Qu.: 4.00        1st Qu.:  0.378   
##  Median :0              Median :10.00        Median :  1.000   
##  Mean   :0              Mean   :13.72        Mean   :  4.388   
##  3rd Qu.:0              3rd Qu.:19.00        3rd Qu.:  3.434   
##  Max.   :0              Max.   :58.00        Max.   :230.428   
##  NA's   :19221                               NA's   :19216     
##  avg_roll_dumbbell stddev_roll_dumbbell var_roll_dumbbell  avg_pitch_dumbbell
##  Min.   :-128.96   Min.   :  0.000      Min.   :    0.00   Min.   :-70.73    
##  1st Qu.: -12.33   1st Qu.:  4.639      1st Qu.:   21.52   1st Qu.:-42.00    
##  Median :  48.23   Median : 12.204      Median :  148.95   Median :-19.91    
##  Mean   :  23.86   Mean   : 20.761      Mean   : 1020.27   Mean   :-12.33    
##  3rd Qu.:  64.37   3rd Qu.: 26.356      3rd Qu.:  694.65   3rd Qu.: 13.21    
##  Max.   : 125.99   Max.   :123.778      Max.   :15321.01   Max.   : 94.28    
##  NA's   :19216     NA's   :19216        NA's   :19216      NA's   :19216     
##  stddev_pitch_dumbbell var_pitch_dumbbell avg_yaw_dumbbell  
##  Min.   : 0.000        Min.   :   0.00    Min.   :-117.950  
##  1st Qu.: 3.482        1st Qu.:  12.12    1st Qu.: -76.696  
##  Median : 8.089        Median :  65.44    Median :  -4.505  
##  Mean   :13.147        Mean   : 350.31    Mean   :   0.202  
##  3rd Qu.:19.238        3rd Qu.: 370.11    3rd Qu.:  71.234  
##  Max.   :82.680        Max.   :6836.02    Max.   : 134.905  
##  NA's   :19216         NA's   :19216      NA's   :19216     
##  stddev_yaw_dumbbell var_yaw_dumbbell   gyros_dumbbell_x    gyros_dumbbell_y  
##  Min.   :  0.000     Min.   :    0.00   Min.   :-204.0000   Min.   :-2.10000  
##  1st Qu.:  3.885     1st Qu.:   15.09   1st Qu.:  -0.0300   1st Qu.:-0.14000  
##  Median : 10.264     Median :  105.35   Median :   0.1300   Median : 0.03000  
##  Mean   : 16.647     Mean   :  589.84   Mean   :   0.1611   Mean   : 0.04606  
##  3rd Qu.: 24.674     3rd Qu.:  608.79   3rd Qu.:   0.3500   3rd Qu.: 0.21000  
##  Max.   :107.088     Max.   :11467.91   Max.   :   2.2200   Max.   :52.00000  
##  NA's   :19216       NA's   :19216                                            
##  gyros_dumbbell_z  accel_dumbbell_x  accel_dumbbell_y  accel_dumbbell_z 
##  Min.   : -2.380   Min.   :-419.00   Min.   :-189.00   Min.   :-334.00  
##  1st Qu.: -0.310   1st Qu.: -50.00   1st Qu.:  -8.00   1st Qu.:-142.00  
##  Median : -0.130   Median :  -8.00   Median :  41.50   Median :  -1.00  
##  Mean   : -0.129   Mean   : -28.62   Mean   :  52.63   Mean   : -38.32  
##  3rd Qu.:  0.030   3rd Qu.:  11.00   3rd Qu.: 111.00   3rd Qu.:  38.00  
##  Max.   :317.000   Max.   : 235.00   Max.   : 315.00   Max.   : 318.00  
##                                                                         
##  magnet_dumbbell_x magnet_dumbbell_y magnet_dumbbell_z  roll_forearm      
##  Min.   :-643.0    Min.   :-3600     Min.   :-262.00   Min.   :-180.0000  
##  1st Qu.:-535.0    1st Qu.:  231     1st Qu.: -45.00   1st Qu.:  -0.7375  
##  Median :-479.0    Median :  311     Median :  13.00   Median :  21.7000  
##  Mean   :-328.5    Mean   :  221     Mean   :  46.05   Mean   :  33.8265  
##  3rd Qu.:-304.0    3rd Qu.:  390     3rd Qu.:  95.00   3rd Qu.: 140.0000  
##  Max.   : 592.0    Max.   :  633     Max.   : 452.00   Max.   : 180.0000  
##                                                                           
##  pitch_forearm     yaw_forearm      kurtosis_roll_forearm
##  Min.   :-72.50   Min.   :-180.00   Min.   :-1.879       
##  1st Qu.:  0.00   1st Qu.: -68.60   1st Qu.:-1.398       
##  Median :  9.24   Median :   0.00   Median :-1.119       
##  Mean   : 10.71   Mean   :  19.21   Mean   :-0.689       
##  3rd Qu.: 28.40   3rd Qu.: 110.00   3rd Qu.:-0.618       
##  Max.   : 89.80   Max.   : 180.00   Max.   :40.060       
##                                     NA's   :19300        
##  kurtosis_picth_forearm kurtosis_yaw_forearm skewness_roll_forearm
##  Min.   :-2.098         Mode:logical         Min.   :-2.297       
##  1st Qu.:-1.376         NA's:19622           1st Qu.:-0.402       
##  Median :-0.890                              Median : 0.003       
##  Mean   : 0.419                              Mean   :-0.009       
##  3rd Qu.: 0.054                              3rd Qu.: 0.370       
##  Max.   :33.626                              Max.   : 5.856       
##  NA's   :19301                               NA's   :19299        
##  skewness_pitch_forearm skewness_yaw_forearm max_roll_forearm max_picth_forearm
##  Min.   :-5.241         Mode:logical         Min.   :-66.60   Min.   :-151.00  
##  1st Qu.:-0.881         NA's:19622           1st Qu.:  0.00   1st Qu.:   0.00  
##  Median :-0.156                              Median : 26.80   Median : 113.00  
##  Mean   :-0.223                              Mean   : 24.49   Mean   :  81.49  
##  3rd Qu.: 0.514                              3rd Qu.: 45.95   3rd Qu.: 174.75  
##  Max.   : 4.464                              Max.   : 89.80   Max.   : 180.00  
##  NA's   :19301                               NA's   :19216    NA's   :19216    
##  max_yaw_forearm  min_roll_forearm  min_pitch_forearm min_yaw_forearm 
##  Min.   :-1.900   Min.   :-72.500   Min.   :-180.00   Min.   :-1.900  
##  1st Qu.:-1.400   1st Qu.: -6.075   1st Qu.:-175.00   1st Qu.:-1.400  
##  Median :-1.100   Median :  0.000   Median : -61.00   Median :-1.100  
##  Mean   :-0.689   Mean   : -0.167   Mean   : -57.57   Mean   :-0.689  
##  3rd Qu.:-0.600   3rd Qu.: 12.075   3rd Qu.:   0.00   3rd Qu.:-0.600  
##  Max.   :40.100   Max.   : 62.100   Max.   : 167.00   Max.   :40.100  
##  NA's   :19300    NA's   :19216     NA's   :19216     NA's   :19300   
##  amplitude_roll_forearm amplitude_pitch_forearm amplitude_yaw_forearm
##  Min.   :  0.000        Min.   :  0.0           Min.   :0            
##  1st Qu.:  1.125        1st Qu.:  2.0           1st Qu.:0            
##  Median : 17.770        Median : 83.7           Median :0            
##  Mean   : 24.653        Mean   :139.1           Mean   :0            
##  3rd Qu.: 39.875        3rd Qu.:350.0           3rd Qu.:0            
##  Max.   :126.000        Max.   :360.0           Max.   :0            
##  NA's   :19216          NA's   :19216           NA's   :19300        
##  total_accel_forearm var_accel_forearm avg_roll_forearm   stddev_roll_forearm
##  Min.   :  0.00      Min.   :  0.000   Min.   :-177.234   Min.   :  0.000    
##  1st Qu.: 29.00      1st Qu.:  6.759   1st Qu.:  -0.909   1st Qu.:  0.428    
##  Median : 36.00      Median : 21.165   Median :  11.172   Median :  8.030    
##  Mean   : 34.72      Mean   : 33.502   Mean   :  33.165   Mean   : 41.986    
##  3rd Qu.: 41.00      3rd Qu.: 51.240   3rd Qu.: 107.132   3rd Qu.: 85.373    
##  Max.   :108.00      Max.   :172.606   Max.   : 177.256   Max.   :179.171    
##                      NA's   :19216     NA's   :19216      NA's   :19216      
##  var_roll_forearm   avg_pitch_forearm stddev_pitch_forearm var_pitch_forearm 
##  Min.   :    0.00   Min.   :-68.17    Min.   : 0.000       Min.   :   0.000  
##  1st Qu.:    0.18   1st Qu.:  0.00    1st Qu.: 0.336       1st Qu.:   0.113  
##  Median :   64.48   Median : 12.02    Median : 5.516       Median :  30.425  
##  Mean   : 5274.10   Mean   : 11.79    Mean   : 7.977       Mean   : 139.593  
##  3rd Qu.: 7289.08   3rd Qu.: 28.48    3rd Qu.:12.866       3rd Qu.: 165.532  
##  Max.   :32102.24   Max.   : 72.09    Max.   :47.745       Max.   :2279.617  
##  NA's   :19216      NA's   :19216     NA's   :19216        NA's   :19216     
##  avg_yaw_forearm   stddev_yaw_forearm var_yaw_forearm    gyros_forearm_x  
##  Min.   :-155.06   Min.   :  0.000    Min.   :    0.00   Min.   :-22.000  
##  1st Qu.: -26.26   1st Qu.:  0.524    1st Qu.:    0.27   1st Qu.: -0.220  
##  Median :   0.00   Median : 24.743    Median :  612.21   Median :  0.050  
##  Mean   :  18.00   Mean   : 44.854    Mean   : 4639.85   Mean   :  0.158  
##  3rd Qu.:  85.79   3rd Qu.: 85.817    3rd Qu.: 7368.41   3rd Qu.:  0.560  
##  Max.   : 169.24   Max.   :197.508    Max.   :39009.33   Max.   :  3.970  
##  NA's   :19216     NA's   :19216      NA's   :19216                       
##  gyros_forearm_y     gyros_forearm_z    accel_forearm_x   accel_forearm_y 
##  Min.   : -7.02000   Min.   : -8.0900   Min.   :-498.00   Min.   :-632.0  
##  1st Qu.: -1.46000   1st Qu.: -0.1800   1st Qu.:-178.00   1st Qu.:  57.0  
##  Median :  0.03000   Median :  0.0800   Median : -57.00   Median : 201.0  
##  Mean   :  0.07517   Mean   :  0.1512   Mean   : -61.65   Mean   : 163.7  
##  3rd Qu.:  1.62000   3rd Qu.:  0.4900   3rd Qu.:  76.00   3rd Qu.: 312.0  
##  Max.   :311.00000   Max.   :231.0000   Max.   : 477.00   Max.   : 923.0  
##                                                                           
##  accel_forearm_z   magnet_forearm_x  magnet_forearm_y magnet_forearm_z
##  Min.   :-446.00   Min.   :-1280.0   Min.   :-896.0   Min.   :-973.0  
##  1st Qu.:-182.00   1st Qu.: -616.0   1st Qu.:   2.0   1st Qu.: 191.0  
##  Median : -39.00   Median : -378.0   Median : 591.0   Median : 511.0  
##  Mean   : -55.29   Mean   : -312.6   Mean   : 380.1   Mean   : 393.6  
##  3rd Qu.:  26.00   3rd Qu.:  -73.0   3rd Qu.: 737.0   3rd Qu.: 653.0  
##  Max.   : 291.00   Max.   :  672.0   Max.   :1480.0   Max.   :1090.0  
##                                                                       
##     classe         
##  Length:19622      
##  Class :character  
##  Mode  :character  
##                    
##                    
##                    
## 

The first part of the Project: data primary analysis

Done:

##        X          user_name         raw_timestamp_part_1 raw_timestamp_part_2
##  Min.   :    1   Length:19622       Min.   :1.322e+09    Min.   :   294      
##  1st Qu.: 4906   Class :character   1st Qu.:1.323e+09    1st Qu.:252912      
##  Median : 9812   Mode  :character   Median :1.323e+09    Median :496380      
##  Mean   : 9812                      Mean   :1.323e+09    Mean   :500656      
##  3rd Qu.:14717                      3rd Qu.:1.323e+09    3rd Qu.:751891      
##  Max.   :19622                      Max.   :1.323e+09    Max.   :998801      
##                                                                              
##  cvtd_timestamp      new_window          num_window      roll_belt     
##  Length:19622       Length:19622       Min.   :  1.0   Min.   :-28.90  
##  Class :character   Class :character   1st Qu.:222.0   1st Qu.:  1.10  
##  Mode  :character   Mode  :character   Median :424.0   Median :113.00  
##                                        Mean   :430.6   Mean   : 64.41  
##                                        3rd Qu.:644.0   3rd Qu.:123.00  
##                                        Max.   :864.0   Max.   :162.00  
##                                                                        
##    pitch_belt          yaw_belt       total_accel_belt kurtosis_roll_belt
##  Min.   :-55.8000   Min.   :-180.00   Min.   : 0.00    Min.   :-2.121    
##  1st Qu.:  1.7600   1st Qu.: -88.30   1st Qu.: 3.00    1st Qu.:-1.329    
##  Median :  5.2800   Median : -13.00   Median :17.00    Median :-0.899    
##  Mean   :  0.3053   Mean   : -11.21   Mean   :11.31    Mean   :-0.220    
##  3rd Qu.: 14.9000   3rd Qu.:  12.90   3rd Qu.:18.00    3rd Qu.:-0.219    
##  Max.   : 60.3000   Max.   : 179.00   Max.   :29.00    Max.   :33.000    
##                                                        NA's   :19226     
##  kurtosis_picth_belt kurtosis_yaw_belt skewness_roll_belt skewness_roll_belt.1
##  Min.   :-2.190      Mode:logical      Min.   :-5.745     Min.   :-7.616      
##  1st Qu.:-1.107      NA's:19622        1st Qu.:-0.444     1st Qu.:-1.114      
##  Median :-0.151                        Median : 0.000     Median :-0.068      
##  Mean   : 4.334                        Mean   :-0.026     Mean   :-0.296      
##  3rd Qu.: 3.178                        3rd Qu.: 0.417     3rd Qu.: 0.661      
##  Max.   :58.000                        Max.   : 3.595     Max.   : 7.348      
##  NA's   :19248                         NA's   :19225      NA's   :19248       
##  skewness_yaw_belt max_roll_belt     max_picth_belt   max_yaw_belt  
##  Mode:logical      Min.   :-94.300   Min.   : 3.00   Min.   :-2.10  
##  NA's:19622        1st Qu.:-88.000   1st Qu.: 5.00   1st Qu.:-1.30  
##                    Median : -5.100   Median :18.00   Median :-0.90  
##                    Mean   : -6.667   Mean   :12.92   Mean   :-0.22  
##                    3rd Qu.: 18.500   3rd Qu.:19.00   3rd Qu.:-0.20  
##                    Max.   :180.000   Max.   :30.00   Max.   :33.00  
##                    NA's   :19216     NA's   :19216   NA's   :19226  
##  min_roll_belt     min_pitch_belt   min_yaw_belt   amplitude_roll_belt
##  Min.   :-180.00   Min.   : 0.00   Min.   :-2.10   Min.   :  0.000    
##  1st Qu.: -88.40   1st Qu.: 3.00   1st Qu.:-1.30   1st Qu.:  0.300    
##  Median :  -7.85   Median :16.00   Median :-0.90   Median :  1.000    
##  Mean   : -10.44   Mean   :10.76   Mean   :-0.22   Mean   :  3.769    
##  3rd Qu.:   9.05   3rd Qu.:17.00   3rd Qu.:-0.20   3rd Qu.:  2.082    
##  Max.   : 173.00   Max.   :23.00   Max.   :33.00   Max.   :360.000    
##  NA's   :19216     NA's   :19216   NA's   :19226   NA's   :19216      
##  amplitude_pitch_belt amplitude_yaw_belt var_total_accel_belt avg_roll_belt   
##  Min.   : 0.000       Min.   :0          Min.   : 0.000       Min.   :-27.40  
##  1st Qu.: 1.000       1st Qu.:0          1st Qu.: 0.100       1st Qu.:  1.10  
##  Median : 1.000       Median :0          Median : 0.200       Median :116.35  
##  Mean   : 2.167       Mean   :0          Mean   : 0.926       Mean   : 68.06  
##  3rd Qu.: 2.000       3rd Qu.:0          3rd Qu.: 0.300       3rd Qu.:123.38  
##  Max.   :12.000       Max.   :0          Max.   :16.500       Max.   :157.40  
##  NA's   :19216        NA's   :19226      NA's   :19216        NA's   :19216   
##  stddev_roll_belt var_roll_belt     avg_pitch_belt    stddev_pitch_belt
##  Min.   : 0.000   Min.   :  0.000   Min.   :-51.400   Min.   :0.000    
##  1st Qu.: 0.200   1st Qu.:  0.000   1st Qu.:  2.025   1st Qu.:0.200    
##  Median : 0.400   Median :  0.100   Median :  5.200   Median :0.400    
##  Mean   : 1.337   Mean   :  7.699   Mean   :  0.520   Mean   :0.603    
##  3rd Qu.: 0.700   3rd Qu.:  0.500   3rd Qu.: 15.775   3rd Qu.:0.700    
##  Max.   :14.200   Max.   :200.700   Max.   : 59.700   Max.   :4.000    
##  NA's   :19216    NA's   :19216     NA's   :19216     NA's   :19216    
##  var_pitch_belt    avg_yaw_belt      stddev_yaw_belt    var_yaw_belt      
##  Min.   : 0.000   Min.   :-138.300   Min.   :  0.000   Min.   :    0.000  
##  1st Qu.: 0.000   1st Qu.: -88.175   1st Qu.:  0.100   1st Qu.:    0.010  
##  Median : 0.100   Median :  -6.550   Median :  0.300   Median :    0.090  
##  Mean   : 0.766   Mean   :  -8.831   Mean   :  1.341   Mean   :  107.487  
##  3rd Qu.: 0.500   3rd Qu.:  14.125   3rd Qu.:  0.700   3rd Qu.:    0.475  
##  Max.   :16.200   Max.   : 173.500   Max.   :176.600   Max.   :31183.240  
##  NA's   :19216    NA's   :19216      NA's   :19216     NA's   :19216      
##   gyros_belt_x        gyros_belt_y       gyros_belt_z      accel_belt_x     
##  Min.   :-1.040000   Min.   :-0.64000   Min.   :-1.4600   Min.   :-120.000  
##  1st Qu.:-0.030000   1st Qu.: 0.00000   1st Qu.:-0.2000   1st Qu.: -21.000  
##  Median : 0.030000   Median : 0.02000   Median :-0.1000   Median : -15.000  
##  Mean   :-0.005592   Mean   : 0.03959   Mean   :-0.1305   Mean   :  -5.595  
##  3rd Qu.: 0.110000   3rd Qu.: 0.11000   3rd Qu.:-0.0200   3rd Qu.:  -5.000  
##  Max.   : 2.220000   Max.   : 0.64000   Max.   : 1.6200   Max.   :  85.000  
##                                                                             
##   accel_belt_y     accel_belt_z     magnet_belt_x   magnet_belt_y  
##  Min.   :-69.00   Min.   :-275.00   Min.   :-52.0   Min.   :354.0  
##  1st Qu.:  3.00   1st Qu.:-162.00   1st Qu.:  9.0   1st Qu.:581.0  
##  Median : 35.00   Median :-152.00   Median : 35.0   Median :601.0  
##  Mean   : 30.15   Mean   : -72.59   Mean   : 55.6   Mean   :593.7  
##  3rd Qu.: 61.00   3rd Qu.:  27.00   3rd Qu.: 59.0   3rd Qu.:610.0  
##  Max.   :164.00   Max.   : 105.00   Max.   :485.0   Max.   :673.0  
##                                                                    
##  magnet_belt_z       roll_arm         pitch_arm          yaw_arm         
##  Min.   :-623.0   Min.   :-180.00   Min.   :-88.800   Min.   :-180.0000  
##  1st Qu.:-375.0   1st Qu.: -31.77   1st Qu.:-25.900   1st Qu.: -43.1000  
##  Median :-320.0   Median :   0.00   Median :  0.000   Median :   0.0000  
##  Mean   :-345.5   Mean   :  17.83   Mean   : -4.612   Mean   :  -0.6188  
##  3rd Qu.:-306.0   3rd Qu.:  77.30   3rd Qu.: 11.200   3rd Qu.:  45.8750  
##  Max.   : 293.0   Max.   : 180.00   Max.   : 88.500   Max.   : 180.0000  
##                                                                          
##  total_accel_arm var_accel_arm     avg_roll_arm     stddev_roll_arm  
##  Min.   : 1.00   Min.   :  0.00   Min.   :-166.67   Min.   :  0.000  
##  1st Qu.:17.00   1st Qu.:  9.03   1st Qu.: -38.37   1st Qu.:  1.376  
##  Median :27.00   Median : 40.61   Median :   0.00   Median :  5.702  
##  Mean   :25.51   Mean   : 53.23   Mean   :  12.68   Mean   : 11.201  
##  3rd Qu.:33.00   3rd Qu.: 75.62   3rd Qu.:  76.33   3rd Qu.: 14.921  
##  Max.   :66.00   Max.   :331.70   Max.   : 163.33   Max.   :161.964  
##                  NA's   :19216    NA's   :19216     NA's   :19216    
##   var_roll_arm       avg_pitch_arm     stddev_pitch_arm var_pitch_arm     
##  Min.   :    0.000   Min.   :-81.773   Min.   : 0.000   Min.   :   0.000  
##  1st Qu.:    1.898   1st Qu.:-22.770   1st Qu.: 1.642   1st Qu.:   2.697  
##  Median :   32.517   Median :  0.000   Median : 8.133   Median :  66.146  
##  Mean   :  417.264   Mean   : -4.901   Mean   :10.383   Mean   : 195.864  
##  3rd Qu.:  222.647   3rd Qu.:  8.277   3rd Qu.:16.327   3rd Qu.: 266.576  
##  Max.   :26232.208   Max.   : 75.659   Max.   :43.412   Max.   :1884.565  
##  NA's   :19216       NA's   :19216     NA's   :19216    NA's   :19216     
##   avg_yaw_arm       stddev_yaw_arm     var_yaw_arm         gyros_arm_x      
##  Min.   :-173.440   Min.   :  0.000   Min.   :    0.000   Min.   :-6.37000  
##  1st Qu.: -29.198   1st Qu.:  2.577   1st Qu.:    6.642   1st Qu.:-1.33000  
##  Median :   0.000   Median : 16.682   Median :  278.309   Median : 0.08000  
##  Mean   :   2.359   Mean   : 22.270   Mean   : 1055.933   Mean   : 0.04277  
##  3rd Qu.:  38.185   3rd Qu.: 35.984   3rd Qu.: 1294.850   3rd Qu.: 1.57000  
##  Max.   : 152.000   Max.   :177.044   Max.   :31344.568   Max.   : 4.87000  
##  NA's   :19216      NA's   :19216     NA's   :19216                         
##   gyros_arm_y       gyros_arm_z       accel_arm_x       accel_arm_y    
##  Min.   :-3.4400   Min.   :-2.3300   Min.   :-404.00   Min.   :-318.0  
##  1st Qu.:-0.8000   1st Qu.:-0.0700   1st Qu.:-242.00   1st Qu.: -54.0  
##  Median :-0.2400   Median : 0.2300   Median : -44.00   Median :  14.0  
##  Mean   :-0.2571   Mean   : 0.2695   Mean   : -60.24   Mean   :  32.6  
##  3rd Qu.: 0.1400   3rd Qu.: 0.7200   3rd Qu.:  84.00   3rd Qu.: 139.0  
##  Max.   : 2.8400   Max.   : 3.0200   Max.   : 437.00   Max.   : 308.0  
##                                                                        
##   accel_arm_z       magnet_arm_x     magnet_arm_y     magnet_arm_z   
##  Min.   :-636.00   Min.   :-584.0   Min.   :-392.0   Min.   :-597.0  
##  1st Qu.:-143.00   1st Qu.:-300.0   1st Qu.:  -9.0   1st Qu.: 131.2  
##  Median : -47.00   Median : 289.0   Median : 202.0   Median : 444.0  
##  Mean   : -71.25   Mean   : 191.7   Mean   : 156.6   Mean   : 306.5  
##  3rd Qu.:  23.00   3rd Qu.: 637.0   3rd Qu.: 323.0   3rd Qu.: 545.0  
##  Max.   : 292.00   Max.   : 782.0   Max.   : 583.0   Max.   : 694.0  
##                                                                      
##  kurtosis_roll_arm kurtosis_picth_arm kurtosis_yaw_arm skewness_roll_arm
##  Min.   :-1.809    Min.   :-2.084     Min.   :-2.103   Min.   :-2.541   
##  1st Qu.:-1.345    1st Qu.:-1.280     1st Qu.:-1.220   1st Qu.:-0.561   
##  Median :-0.894    Median :-1.010     Median :-0.733   Median : 0.040   
##  Mean   :-0.366    Mean   :-0.542     Mean   : 0.406   Mean   : 0.068   
##  3rd Qu.:-0.038    3rd Qu.:-0.379     3rd Qu.: 0.115   3rd Qu.: 0.671   
##  Max.   :21.456    Max.   :19.751     Max.   :56.000   Max.   : 4.394   
##  NA's   :19294     NA's   :19296      NA's   :19227    NA's   :19293    
##  skewness_pitch_arm skewness_yaw_arm  max_roll_arm     max_picth_arm     
##  Min.   :-4.565     Min.   :-6.708   Min.   :-73.100   Min.   :-173.000  
##  1st Qu.:-0.618     1st Qu.:-0.743   1st Qu.: -0.175   1st Qu.:  -1.975  
##  Median :-0.035     Median :-0.133   Median :  4.950   Median :  23.250  
##  Mean   :-0.065     Mean   :-0.229   Mean   : 11.236   Mean   :  35.751  
##  3rd Qu.: 0.454     3rd Qu.: 0.344   3rd Qu.: 26.775   3rd Qu.:  95.975  
##  Max.   : 3.043     Max.   : 7.483   Max.   : 85.500   Max.   : 180.000  
##  NA's   :19296      NA's   :19227    NA's   :19216     NA's   :19216     
##   max_yaw_arm     min_roll_arm    min_pitch_arm      min_yaw_arm   
##  Min.   : 4.00   Min.   :-89.10   Min.   :-180.00   Min.   : 1.00  
##  1st Qu.:29.00   1st Qu.:-41.98   1st Qu.: -72.62   1st Qu.: 8.00  
##  Median :34.00   Median :-22.45   Median : -33.85   Median :13.00  
##  Mean   :35.46   Mean   :-21.22   Mean   : -33.92   Mean   :14.66  
##  3rd Qu.:41.00   3rd Qu.:  0.00   3rd Qu.:   0.00   3rd Qu.:19.00  
##  Max.   :65.00   Max.   : 66.40   Max.   : 152.00   Max.   :38.00  
##  NA's   :19216   NA's   :19216    NA's   :19216     NA's   :19216  
##  amplitude_roll_arm amplitude_pitch_arm amplitude_yaw_arm roll_dumbbell    
##  Min.   :  0.000    Min.   :  0.000     Min.   : 0.00     Min.   :-153.71  
##  1st Qu.:  5.425    1st Qu.:  9.925     1st Qu.:13.00     1st Qu.: -18.49  
##  Median : 28.450    Median : 54.900     Median :22.00     Median :  48.17  
##  Mean   : 32.452    Mean   : 69.677     Mean   :20.79     Mean   :  23.84  
##  3rd Qu.: 50.960    3rd Qu.:115.175     3rd Qu.:28.75     3rd Qu.:  67.61  
##  Max.   :119.500    Max.   :360.000     Max.   :52.00     Max.   : 153.55  
##  NA's   :19216      NA's   :19216       NA's   :19216                      
##  pitch_dumbbell     yaw_dumbbell      kurtosis_roll_dumbbell
##  Min.   :-149.59   Min.   :-150.871   Min.   :-2.174        
##  1st Qu.: -40.89   1st Qu.: -77.644   1st Qu.:-0.682        
##  Median : -20.96   Median :  -3.324   Median :-0.033        
##  Mean   : -10.78   Mean   :   1.674   Mean   : 0.452        
##  3rd Qu.:  17.50   3rd Qu.:  79.643   3rd Qu.: 0.940        
##  Max.   : 149.40   Max.   : 154.952   Max.   :54.998        
##                                       NA's   :19221         
##  kurtosis_picth_dumbbell kurtosis_yaw_dumbbell skewness_roll_dumbbell
##  Min.   :-2.200          Mode:logical          Min.   :-7.384        
##  1st Qu.:-0.721          NA's:19622            1st Qu.:-0.581        
##  Median :-0.133                                Median :-0.076        
##  Mean   : 0.286                                Mean   :-0.115        
##  3rd Qu.: 0.584                                3rd Qu.: 0.400        
##  Max.   :55.628                                Max.   : 1.958        
##  NA's   :19218                                 NA's   :19220         
##  skewness_pitch_dumbbell skewness_yaw_dumbbell max_roll_dumbbell
##  Min.   :-7.447          Mode:logical          Min.   :-70.10   
##  1st Qu.:-0.525          NA's:19622            1st Qu.:-27.15   
##  Median :-0.091                                Median : 14.85   
##  Mean   :-0.035                                Mean   : 13.76   
##  3rd Qu.: 0.505                                3rd Qu.: 50.58   
##  Max.   : 3.769                                Max.   :137.00   
##  NA's   :19217                                 NA's   :19216    
##  max_picth_dumbbell max_yaw_dumbbell min_roll_dumbbell min_pitch_dumbbell
##  Min.   :-112.90    Min.   :-2.20    Min.   :-149.60   Min.   :-147.00   
##  1st Qu.: -66.70    1st Qu.:-0.70    1st Qu.: -59.67   1st Qu.: -91.80   
##  Median :  40.05    Median : 0.00    Median : -43.55   Median : -66.15   
##  Mean   :  32.75    Mean   : 0.45    Mean   : -41.24   Mean   : -33.18   
##  3rd Qu.: 133.22    3rd Qu.: 0.90    3rd Qu.: -25.20   3rd Qu.:  21.20   
##  Max.   : 155.00    Max.   :55.00    Max.   :  73.20   Max.   : 120.90   
##  NA's   :19216      NA's   :19221    NA's   :19216     NA's   :19216     
##  min_yaw_dumbbell amplitude_roll_dumbbell amplitude_pitch_dumbbell
##  Min.   :-2.20    Min.   :  0.00          Min.   :  0.00          
##  1st Qu.:-0.70    1st Qu.: 14.97          1st Qu.: 17.06          
##  Median : 0.00    Median : 35.05          Median : 41.73          
##  Mean   : 0.45    Mean   : 55.00          Mean   : 65.93          
##  3rd Qu.: 0.90    3rd Qu.: 81.04          3rd Qu.: 99.55          
##  Max.   :55.00    Max.   :256.48          Max.   :273.59          
##  NA's   :19221    NA's   :19216           NA's   :19216           
##  amplitude_yaw_dumbbell total_accel_dumbbell var_accel_dumbbell
##  Min.   :0              Min.   : 0.00        Min.   :  0.000   
##  1st Qu.:0              1st Qu.: 4.00        1st Qu.:  0.378   
##  Median :0              Median :10.00        Median :  1.000   
##  Mean   :0              Mean   :13.72        Mean   :  4.388   
##  3rd Qu.:0              3rd Qu.:19.00        3rd Qu.:  3.434   
##  Max.   :0              Max.   :58.00        Max.   :230.428   
##  NA's   :19221                               NA's   :19216     
##  avg_roll_dumbbell stddev_roll_dumbbell var_roll_dumbbell  avg_pitch_dumbbell
##  Min.   :-128.96   Min.   :  0.000      Min.   :    0.00   Min.   :-70.73    
##  1st Qu.: -12.33   1st Qu.:  4.639      1st Qu.:   21.52   1st Qu.:-42.00    
##  Median :  48.23   Median : 12.204      Median :  148.95   Median :-19.91    
##  Mean   :  23.86   Mean   : 20.761      Mean   : 1020.27   Mean   :-12.33    
##  3rd Qu.:  64.37   3rd Qu.: 26.356      3rd Qu.:  694.65   3rd Qu.: 13.21    
##  Max.   : 125.99   Max.   :123.778      Max.   :15321.01   Max.   : 94.28    
##  NA's   :19216     NA's   :19216        NA's   :19216      NA's   :19216     
##  stddev_pitch_dumbbell var_pitch_dumbbell avg_yaw_dumbbell  
##  Min.   : 0.000        Min.   :   0.00    Min.   :-117.950  
##  1st Qu.: 3.482        1st Qu.:  12.12    1st Qu.: -76.696  
##  Median : 8.089        Median :  65.44    Median :  -4.505  
##  Mean   :13.147        Mean   : 350.31    Mean   :   0.202  
##  3rd Qu.:19.238        3rd Qu.: 370.11    3rd Qu.:  71.234  
##  Max.   :82.680        Max.   :6836.02    Max.   : 134.905  
##  NA's   :19216         NA's   :19216      NA's   :19216     
##  stddev_yaw_dumbbell var_yaw_dumbbell   gyros_dumbbell_x    gyros_dumbbell_y  
##  Min.   :  0.000     Min.   :    0.00   Min.   :-204.0000   Min.   :-2.10000  
##  1st Qu.:  3.885     1st Qu.:   15.09   1st Qu.:  -0.0300   1st Qu.:-0.14000  
##  Median : 10.264     Median :  105.35   Median :   0.1300   Median : 0.03000  
##  Mean   : 16.647     Mean   :  589.84   Mean   :   0.1611   Mean   : 0.04606  
##  3rd Qu.: 24.674     3rd Qu.:  608.79   3rd Qu.:   0.3500   3rd Qu.: 0.21000  
##  Max.   :107.088     Max.   :11467.91   Max.   :   2.2200   Max.   :52.00000  
##  NA's   :19216       NA's   :19216                                            
##  gyros_dumbbell_z  accel_dumbbell_x  accel_dumbbell_y  accel_dumbbell_z 
##  Min.   : -2.380   Min.   :-419.00   Min.   :-189.00   Min.   :-334.00  
##  1st Qu.: -0.310   1st Qu.: -50.00   1st Qu.:  -8.00   1st Qu.:-142.00  
##  Median : -0.130   Median :  -8.00   Median :  41.50   Median :  -1.00  
##  Mean   : -0.129   Mean   : -28.62   Mean   :  52.63   Mean   : -38.32  
##  3rd Qu.:  0.030   3rd Qu.:  11.00   3rd Qu.: 111.00   3rd Qu.:  38.00  
##  Max.   :317.000   Max.   : 235.00   Max.   : 315.00   Max.   : 318.00  
##                                                                         
##  magnet_dumbbell_x magnet_dumbbell_y magnet_dumbbell_z  roll_forearm      
##  Min.   :-643.0    Min.   :-3600     Min.   :-262.00   Min.   :-180.0000  
##  1st Qu.:-535.0    1st Qu.:  231     1st Qu.: -45.00   1st Qu.:  -0.7375  
##  Median :-479.0    Median :  311     Median :  13.00   Median :  21.7000  
##  Mean   :-328.5    Mean   :  221     Mean   :  46.05   Mean   :  33.8265  
##  3rd Qu.:-304.0    3rd Qu.:  390     3rd Qu.:  95.00   3rd Qu.: 140.0000  
##  Max.   : 592.0    Max.   :  633     Max.   : 452.00   Max.   : 180.0000  
##                                                                           
##  pitch_forearm     yaw_forearm      kurtosis_roll_forearm
##  Min.   :-72.50   Min.   :-180.00   Min.   :-1.879       
##  1st Qu.:  0.00   1st Qu.: -68.60   1st Qu.:-1.398       
##  Median :  9.24   Median :   0.00   Median :-1.119       
##  Mean   : 10.71   Mean   :  19.21   Mean   :-0.689       
##  3rd Qu.: 28.40   3rd Qu.: 110.00   3rd Qu.:-0.618       
##  Max.   : 89.80   Max.   : 180.00   Max.   :40.060       
##                                     NA's   :19300        
##  kurtosis_picth_forearm kurtosis_yaw_forearm skewness_roll_forearm
##  Min.   :-2.098         Mode:logical         Min.   :-2.297       
##  1st Qu.:-1.376         NA's:19622           1st Qu.:-0.402       
##  Median :-0.890                              Median : 0.003       
##  Mean   : 0.419                              Mean   :-0.009       
##  3rd Qu.: 0.054                              3rd Qu.: 0.370       
##  Max.   :33.626                              Max.   : 5.856       
##  NA's   :19301                               NA's   :19299        
##  skewness_pitch_forearm skewness_yaw_forearm max_roll_forearm max_picth_forearm
##  Min.   :-5.241         Mode:logical         Min.   :-66.60   Min.   :-151.00  
##  1st Qu.:-0.881         NA's:19622           1st Qu.:  0.00   1st Qu.:   0.00  
##  Median :-0.156                              Median : 26.80   Median : 113.00  
##  Mean   :-0.223                              Mean   : 24.49   Mean   :  81.49  
##  3rd Qu.: 0.514                              3rd Qu.: 45.95   3rd Qu.: 174.75  
##  Max.   : 4.464                              Max.   : 89.80   Max.   : 180.00  
##  NA's   :19301                               NA's   :19216    NA's   :19216    
##  max_yaw_forearm  min_roll_forearm  min_pitch_forearm min_yaw_forearm 
##  Min.   :-1.900   Min.   :-72.500   Min.   :-180.00   Min.   :-1.900  
##  1st Qu.:-1.400   1st Qu.: -6.075   1st Qu.:-175.00   1st Qu.:-1.400  
##  Median :-1.100   Median :  0.000   Median : -61.00   Median :-1.100  
##  Mean   :-0.689   Mean   : -0.167   Mean   : -57.57   Mean   :-0.689  
##  3rd Qu.:-0.600   3rd Qu.: 12.075   3rd Qu.:   0.00   3rd Qu.:-0.600  
##  Max.   :40.100   Max.   : 62.100   Max.   : 167.00   Max.   :40.100  
##  NA's   :19300    NA's   :19216     NA's   :19216     NA's   :19300   
##  amplitude_roll_forearm amplitude_pitch_forearm amplitude_yaw_forearm
##  Min.   :  0.000        Min.   :  0.0           Min.   :0            
##  1st Qu.:  1.125        1st Qu.:  2.0           1st Qu.:0            
##  Median : 17.770        Median : 83.7           Median :0            
##  Mean   : 24.653        Mean   :139.1           Mean   :0            
##  3rd Qu.: 39.875        3rd Qu.:350.0           3rd Qu.:0            
##  Max.   :126.000        Max.   :360.0           Max.   :0            
##  NA's   :19216          NA's   :19216           NA's   :19300        
##  total_accel_forearm var_accel_forearm avg_roll_forearm   stddev_roll_forearm
##  Min.   :  0.00      Min.   :  0.000   Min.   :-177.234   Min.   :  0.000    
##  1st Qu.: 29.00      1st Qu.:  6.759   1st Qu.:  -0.909   1st Qu.:  0.428    
##  Median : 36.00      Median : 21.165   Median :  11.172   Median :  8.030    
##  Mean   : 34.72      Mean   : 33.502   Mean   :  33.165   Mean   : 41.986    
##  3rd Qu.: 41.00      3rd Qu.: 51.240   3rd Qu.: 107.132   3rd Qu.: 85.373    
##  Max.   :108.00      Max.   :172.606   Max.   : 177.256   Max.   :179.171    
##                      NA's   :19216     NA's   :19216      NA's   :19216      
##  var_roll_forearm   avg_pitch_forearm stddev_pitch_forearm var_pitch_forearm 
##  Min.   :    0.00   Min.   :-68.17    Min.   : 0.000       Min.   :   0.000  
##  1st Qu.:    0.18   1st Qu.:  0.00    1st Qu.: 0.336       1st Qu.:   0.113  
##  Median :   64.48   Median : 12.02    Median : 5.516       Median :  30.425  
##  Mean   : 5274.10   Mean   : 11.79    Mean   : 7.977       Mean   : 139.593  
##  3rd Qu.: 7289.08   3rd Qu.: 28.48    3rd Qu.:12.866       3rd Qu.: 165.532  
##  Max.   :32102.24   Max.   : 72.09    Max.   :47.745       Max.   :2279.617  
##  NA's   :19216      NA's   :19216     NA's   :19216        NA's   :19216     
##  avg_yaw_forearm   stddev_yaw_forearm var_yaw_forearm    gyros_forearm_x  
##  Min.   :-155.06   Min.   :  0.000    Min.   :    0.00   Min.   :-22.000  
##  1st Qu.: -26.26   1st Qu.:  0.524    1st Qu.:    0.27   1st Qu.: -0.220  
##  Median :   0.00   Median : 24.743    Median :  612.21   Median :  0.050  
##  Mean   :  18.00   Mean   : 44.854    Mean   : 4639.85   Mean   :  0.158  
##  3rd Qu.:  85.79   3rd Qu.: 85.817    3rd Qu.: 7368.41   3rd Qu.:  0.560  
##  Max.   : 169.24   Max.   :197.508    Max.   :39009.33   Max.   :  3.970  
##  NA's   :19216     NA's   :19216      NA's   :19216                       
##  gyros_forearm_y     gyros_forearm_z    accel_forearm_x   accel_forearm_y 
##  Min.   : -7.02000   Min.   : -8.0900   Min.   :-498.00   Min.   :-632.0  
##  1st Qu.: -1.46000   1st Qu.: -0.1800   1st Qu.:-178.00   1st Qu.:  57.0  
##  Median :  0.03000   Median :  0.0800   Median : -57.00   Median : 201.0  
##  Mean   :  0.07517   Mean   :  0.1512   Mean   : -61.65   Mean   : 163.7  
##  3rd Qu.:  1.62000   3rd Qu.:  0.4900   3rd Qu.:  76.00   3rd Qu.: 312.0  
##  Max.   :311.00000   Max.   :231.0000   Max.   : 477.00   Max.   : 923.0  
##                                                                           
##  accel_forearm_z   magnet_forearm_x  magnet_forearm_y magnet_forearm_z
##  Min.   :-446.00   Min.   :-1280.0   Min.   :-896.0   Min.   :-973.0  
##  1st Qu.:-182.00   1st Qu.: -616.0   1st Qu.:   2.0   1st Qu.: 191.0  
##  Median : -39.00   Median : -378.0   Median : 591.0   Median : 511.0  
##  Mean   : -55.29   Mean   : -312.6   Mean   : 380.1   Mean   : 393.6  
##  3rd Qu.:  26.00   3rd Qu.:  -73.0   3rd Qu.: 737.0   3rd Qu.: 653.0  
##  Max.   : 291.00   Max.   :  672.0   Max.   :1480.0   Max.   :1090.0  
##                                                                       
##     classe         
##  Length:19622      
##  Class :character  
##  Mode  :character  
##                    
##                    
##                    
## 
## 'data.frame':    19622 obs. of  160 variables:
##  $ X                       : int  1 2 3 4 5 6 7 8 9 10 ...
##  $ user_name               : chr  "carlitos" "carlitos" "carlitos" "carlitos" ...
##  $ raw_timestamp_part_1    : int  1323084231 1323084231 1323084231 1323084232 1323084232 1323084232 1323084232 1323084232 1323084232 1323084232 ...
##  $ raw_timestamp_part_2    : int  788290 808298 820366 120339 196328 304277 368296 440390 484323 484434 ...
##  $ cvtd_timestamp          : chr  "05/12/2011 11:23" "05/12/2011 11:23" "05/12/2011 11:23" "05/12/2011 11:23" ...
##  $ new_window              : chr  "no" "no" "no" "no" ...
##  $ num_window              : int  11 11 11 12 12 12 12 12 12 12 ...
##  $ roll_belt               : num  1.41 1.41 1.42 1.48 1.48 1.45 1.42 1.42 1.43 1.45 ...
##  $ pitch_belt              : num  8.07 8.07 8.07 8.05 8.07 8.06 8.09 8.13 8.16 8.17 ...
##  $ yaw_belt                : num  -94.4 -94.4 -94.4 -94.4 -94.4 -94.4 -94.4 -94.4 -94.4 -94.4 ...
##  $ total_accel_belt        : int  3 3 3 3 3 3 3 3 3 3 ...
##  $ kurtosis_roll_belt      : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ kurtosis_picth_belt     : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ kurtosis_yaw_belt       : logi  NA NA NA NA NA NA ...
##  $ skewness_roll_belt      : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ skewness_roll_belt.1    : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ skewness_yaw_belt       : logi  NA NA NA NA NA NA ...
##  $ max_roll_belt           : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ max_picth_belt          : int  NA NA NA NA NA NA NA NA NA NA ...
##  $ max_yaw_belt            : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ min_roll_belt           : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ min_pitch_belt          : int  NA NA NA NA NA NA NA NA NA NA ...
##  $ min_yaw_belt            : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ amplitude_roll_belt     : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ amplitude_pitch_belt    : int  NA NA NA NA NA NA NA NA NA NA ...
##  $ amplitude_yaw_belt      : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ var_total_accel_belt    : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ avg_roll_belt           : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ stddev_roll_belt        : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ var_roll_belt           : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ avg_pitch_belt          : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ stddev_pitch_belt       : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ var_pitch_belt          : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ avg_yaw_belt            : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ stddev_yaw_belt         : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ var_yaw_belt            : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ gyros_belt_x            : num  0 0.02 0 0.02 0.02 0.02 0.02 0.02 0.02 0.03 ...
##  $ gyros_belt_y            : num  0 0 0 0 0.02 0 0 0 0 0 ...
##  $ gyros_belt_z            : num  -0.02 -0.02 -0.02 -0.03 -0.02 -0.02 -0.02 -0.02 -0.02 0 ...
##  $ accel_belt_x            : int  -21 -22 -20 -22 -21 -21 -22 -22 -20 -21 ...
##  $ accel_belt_y            : int  4 4 5 3 2 4 3 4 2 4 ...
##  $ accel_belt_z            : int  22 22 23 21 24 21 21 21 24 22 ...
##  $ magnet_belt_x           : int  -3 -7 -2 -6 -6 0 -4 -2 1 -3 ...
##  $ magnet_belt_y           : int  599 608 600 604 600 603 599 603 602 609 ...
##  $ magnet_belt_z           : int  -313 -311 -305 -310 -302 -312 -311 -313 -312 -308 ...
##  $ roll_arm                : num  -128 -128 -128 -128 -128 -128 -128 -128 -128 -128 ...
##  $ pitch_arm               : num  22.5 22.5 22.5 22.1 22.1 22 21.9 21.8 21.7 21.6 ...
##  $ yaw_arm                 : num  -161 -161 -161 -161 -161 -161 -161 -161 -161 -161 ...
##  $ total_accel_arm         : int  34 34 34 34 34 34 34 34 34 34 ...
##  $ var_accel_arm           : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ avg_roll_arm            : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ stddev_roll_arm         : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ var_roll_arm            : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ avg_pitch_arm           : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ stddev_pitch_arm        : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ var_pitch_arm           : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ avg_yaw_arm             : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ stddev_yaw_arm          : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ var_yaw_arm             : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ gyros_arm_x             : num  0 0.02 0.02 0.02 0 0.02 0 0.02 0.02 0.02 ...
##  $ gyros_arm_y             : num  0 -0.02 -0.02 -0.03 -0.03 -0.03 -0.03 -0.02 -0.03 -0.03 ...
##  $ gyros_arm_z             : num  -0.02 -0.02 -0.02 0.02 0 0 0 0 -0.02 -0.02 ...
##  $ accel_arm_x             : int  -288 -290 -289 -289 -289 -289 -289 -289 -288 -288 ...
##  $ accel_arm_y             : int  109 110 110 111 111 111 111 111 109 110 ...
##  $ accel_arm_z             : int  -123 -125 -126 -123 -123 -122 -125 -124 -122 -124 ...
##  $ magnet_arm_x            : int  -368 -369 -368 -372 -374 -369 -373 -372 -369 -376 ...
##  $ magnet_arm_y            : int  337 337 344 344 337 342 336 338 341 334 ...
##  $ magnet_arm_z            : int  516 513 513 512 506 513 509 510 518 516 ...
##  $ kurtosis_roll_arm       : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ kurtosis_picth_arm      : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ kurtosis_yaw_arm        : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ skewness_roll_arm       : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ skewness_pitch_arm      : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ skewness_yaw_arm        : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ max_roll_arm            : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ max_picth_arm           : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ max_yaw_arm             : int  NA NA NA NA NA NA NA NA NA NA ...
##  $ min_roll_arm            : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ min_pitch_arm           : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ min_yaw_arm             : int  NA NA NA NA NA NA NA NA NA NA ...
##  $ amplitude_roll_arm      : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ amplitude_pitch_arm     : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ amplitude_yaw_arm       : int  NA NA NA NA NA NA NA NA NA NA ...
##  $ roll_dumbbell           : num  13.1 13.1 12.9 13.4 13.4 ...
##  $ pitch_dumbbell          : num  -70.5 -70.6 -70.3 -70.4 -70.4 ...
##  $ yaw_dumbbell            : num  -84.9 -84.7 -85.1 -84.9 -84.9 ...
##  $ kurtosis_roll_dumbbell  : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ kurtosis_picth_dumbbell : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ kurtosis_yaw_dumbbell   : logi  NA NA NA NA NA NA ...
##  $ skewness_roll_dumbbell  : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ skewness_pitch_dumbbell : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ skewness_yaw_dumbbell   : logi  NA NA NA NA NA NA ...
##  $ max_roll_dumbbell       : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ max_picth_dumbbell      : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ max_yaw_dumbbell        : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ min_roll_dumbbell       : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ min_pitch_dumbbell      : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ min_yaw_dumbbell        : num  NA NA NA NA NA NA NA NA NA NA ...
##  $ amplitude_roll_dumbbell : num  NA NA NA NA NA NA NA NA NA NA ...
##   [list output truncated]
##     X user_name raw_timestamp_part_1 raw_timestamp_part_2   cvtd_timestamp
## 1   1  carlitos           1323084231               788290 05/12/2011 11:23
## 2   2  carlitos           1323084231               808298 05/12/2011 11:23
## 3   3  carlitos           1323084231               820366 05/12/2011 11:23
## 4   4  carlitos           1323084232               120339 05/12/2011 11:23
## 5   5  carlitos           1323084232               196328 05/12/2011 11:23
## 6   6  carlitos           1323084232               304277 05/12/2011 11:23
## 7   7  carlitos           1323084232               368296 05/12/2011 11:23
## 8   8  carlitos           1323084232               440390 05/12/2011 11:23
## 9   9  carlitos           1323084232               484323 05/12/2011 11:23
## 10 10  carlitos           1323084232               484434 05/12/2011 11:23
##    new_window num_window roll_belt pitch_belt yaw_belt total_accel_belt
## 1          no         11      1.41       8.07    -94.4                3
## 2          no         11      1.41       8.07    -94.4                3
## 3          no         11      1.42       8.07    -94.4                3
## 4          no         12      1.48       8.05    -94.4                3
## 5          no         12      1.48       8.07    -94.4                3
## 6          no         12      1.45       8.06    -94.4                3
## 7          no         12      1.42       8.09    -94.4                3
## 8          no         12      1.42       8.13    -94.4                3
## 9          no         12      1.43       8.16    -94.4                3
## 10         no         12      1.45       8.17    -94.4                3
##    kurtosis_roll_belt kurtosis_picth_belt kurtosis_yaw_belt skewness_roll_belt
## 1                  NA                  NA                NA                 NA
## 2                  NA                  NA                NA                 NA
## 3                  NA                  NA                NA                 NA
## 4                  NA                  NA                NA                 NA
## 5                  NA                  NA                NA                 NA
## 6                  NA                  NA                NA                 NA
## 7                  NA                  NA                NA                 NA
## 8                  NA                  NA                NA                 NA
## 9                  NA                  NA                NA                 NA
## 10                 NA                  NA                NA                 NA
##    skewness_roll_belt.1 skewness_yaw_belt max_roll_belt max_picth_belt
## 1                    NA                NA            NA             NA
## 2                    NA                NA            NA             NA
## 3                    NA                NA            NA             NA
## 4                    NA                NA            NA             NA
## 5                    NA                NA            NA             NA
## 6                    NA                NA            NA             NA
## 7                    NA                NA            NA             NA
## 8                    NA                NA            NA             NA
## 9                    NA                NA            NA             NA
## 10                   NA                NA            NA             NA
##    max_yaw_belt min_roll_belt min_pitch_belt min_yaw_belt amplitude_roll_belt
## 1            NA            NA             NA           NA                  NA
## 2            NA            NA             NA           NA                  NA
## 3            NA            NA             NA           NA                  NA
## 4            NA            NA             NA           NA                  NA
## 5            NA            NA             NA           NA                  NA
## 6            NA            NA             NA           NA                  NA
## 7            NA            NA             NA           NA                  NA
## 8            NA            NA             NA           NA                  NA
## 9            NA            NA             NA           NA                  NA
## 10           NA            NA             NA           NA                  NA
##    amplitude_pitch_belt amplitude_yaw_belt var_total_accel_belt avg_roll_belt
## 1                    NA                 NA                   NA            NA
## 2                    NA                 NA                   NA            NA
## 3                    NA                 NA                   NA            NA
## 4                    NA                 NA                   NA            NA
## 5                    NA                 NA                   NA            NA
## 6                    NA                 NA                   NA            NA
## 7                    NA                 NA                   NA            NA
## 8                    NA                 NA                   NA            NA
## 9                    NA                 NA                   NA            NA
## 10                   NA                 NA                   NA            NA
##    stddev_roll_belt var_roll_belt avg_pitch_belt stddev_pitch_belt
## 1                NA            NA             NA                NA
## 2                NA            NA             NA                NA
## 3                NA            NA             NA                NA
## 4                NA            NA             NA                NA
## 5                NA            NA             NA                NA
## 6                NA            NA             NA                NA
## 7                NA            NA             NA                NA
## 8                NA            NA             NA                NA
## 9                NA            NA             NA                NA
## 10               NA            NA             NA                NA
##    var_pitch_belt avg_yaw_belt stddev_yaw_belt var_yaw_belt gyros_belt_x
## 1              NA           NA              NA           NA         0.00
## 2              NA           NA              NA           NA         0.02
## 3              NA           NA              NA           NA         0.00
## 4              NA           NA              NA           NA         0.02
## 5              NA           NA              NA           NA         0.02
## 6              NA           NA              NA           NA         0.02
## 7              NA           NA              NA           NA         0.02
## 8              NA           NA              NA           NA         0.02
## 9              NA           NA              NA           NA         0.02
## 10             NA           NA              NA           NA         0.03
##    gyros_belt_y gyros_belt_z accel_belt_x accel_belt_y accel_belt_z
## 1          0.00        -0.02          -21            4           22
## 2          0.00        -0.02          -22            4           22
## 3          0.00        -0.02          -20            5           23
## 4          0.00        -0.03          -22            3           21
## 5          0.02        -0.02          -21            2           24
## 6          0.00        -0.02          -21            4           21
## 7          0.00        -0.02          -22            3           21
## 8          0.00        -0.02          -22            4           21
## 9          0.00        -0.02          -20            2           24
## 10         0.00         0.00          -21            4           22
##    magnet_belt_x magnet_belt_y magnet_belt_z roll_arm pitch_arm yaw_arm
## 1             -3           599          -313     -128      22.5    -161
## 2             -7           608          -311     -128      22.5    -161
## 3             -2           600          -305     -128      22.5    -161
## 4             -6           604          -310     -128      22.1    -161
## 5             -6           600          -302     -128      22.1    -161
## 6              0           603          -312     -128      22.0    -161
## 7             -4           599          -311     -128      21.9    -161
## 8             -2           603          -313     -128      21.8    -161
## 9              1           602          -312     -128      21.7    -161
## 10            -3           609          -308     -128      21.6    -161
##    total_accel_arm var_accel_arm avg_roll_arm stddev_roll_arm var_roll_arm
## 1               34            NA           NA              NA           NA
## 2               34            NA           NA              NA           NA
## 3               34            NA           NA              NA           NA
## 4               34            NA           NA              NA           NA
## 5               34            NA           NA              NA           NA
## 6               34            NA           NA              NA           NA
## 7               34            NA           NA              NA           NA
## 8               34            NA           NA              NA           NA
## 9               34            NA           NA              NA           NA
## 10              34            NA           NA              NA           NA
##    avg_pitch_arm stddev_pitch_arm var_pitch_arm avg_yaw_arm stddev_yaw_arm
## 1             NA               NA            NA          NA             NA
## 2             NA               NA            NA          NA             NA
## 3             NA               NA            NA          NA             NA
## 4             NA               NA            NA          NA             NA
## 5             NA               NA            NA          NA             NA
## 6             NA               NA            NA          NA             NA
## 7             NA               NA            NA          NA             NA
## 8             NA               NA            NA          NA             NA
## 9             NA               NA            NA          NA             NA
## 10            NA               NA            NA          NA             NA
##    var_yaw_arm gyros_arm_x gyros_arm_y gyros_arm_z accel_arm_x accel_arm_y
## 1           NA        0.00        0.00       -0.02        -288         109
## 2           NA        0.02       -0.02       -0.02        -290         110
## 3           NA        0.02       -0.02       -0.02        -289         110
## 4           NA        0.02       -0.03        0.02        -289         111
## 5           NA        0.00       -0.03        0.00        -289         111
## 6           NA        0.02       -0.03        0.00        -289         111
## 7           NA        0.00       -0.03        0.00        -289         111
## 8           NA        0.02       -0.02        0.00        -289         111
## 9           NA        0.02       -0.03       -0.02        -288         109
## 10          NA        0.02       -0.03       -0.02        -288         110
##    accel_arm_z magnet_arm_x magnet_arm_y magnet_arm_z kurtosis_roll_arm
## 1         -123         -368          337          516                NA
## 2         -125         -369          337          513                NA
## 3         -126         -368          344          513                NA
## 4         -123         -372          344          512                NA
## 5         -123         -374          337          506                NA
## 6         -122         -369          342          513                NA
## 7         -125         -373          336          509                NA
## 8         -124         -372          338          510                NA
## 9         -122         -369          341          518                NA
## 10        -124         -376          334          516                NA
##    kurtosis_picth_arm kurtosis_yaw_arm skewness_roll_arm skewness_pitch_arm
## 1                  NA               NA                NA                 NA
## 2                  NA               NA                NA                 NA
## 3                  NA               NA                NA                 NA
## 4                  NA               NA                NA                 NA
## 5                  NA               NA                NA                 NA
## 6                  NA               NA                NA                 NA
## 7                  NA               NA                NA                 NA
## 8                  NA               NA                NA                 NA
## 9                  NA               NA                NA                 NA
## 10                 NA               NA                NA                 NA
##    skewness_yaw_arm max_roll_arm max_picth_arm max_yaw_arm min_roll_arm
## 1                NA           NA            NA          NA           NA
## 2                NA           NA            NA          NA           NA
## 3                NA           NA            NA          NA           NA
## 4                NA           NA            NA          NA           NA
## 5                NA           NA            NA          NA           NA
## 6                NA           NA            NA          NA           NA
## 7                NA           NA            NA          NA           NA
## 8                NA           NA            NA          NA           NA
## 9                NA           NA            NA          NA           NA
## 10               NA           NA            NA          NA           NA
##    min_pitch_arm min_yaw_arm amplitude_roll_arm amplitude_pitch_arm
## 1             NA          NA                 NA                  NA
## 2             NA          NA                 NA                  NA
## 3             NA          NA                 NA                  NA
## 4             NA          NA                 NA                  NA
## 5             NA          NA                 NA                  NA
## 6             NA          NA                 NA                  NA
## 7             NA          NA                 NA                  NA
## 8             NA          NA                 NA                  NA
## 9             NA          NA                 NA                  NA
## 10            NA          NA                 NA                  NA
##    amplitude_yaw_arm roll_dumbbell pitch_dumbbell yaw_dumbbell
## 1                 NA      13.05217      -70.49400    -84.87394
## 2                 NA      13.13074      -70.63751    -84.71065
## 3                 NA      12.85075      -70.27812    -85.14078
## 4                 NA      13.43120      -70.39379    -84.87363
## 5                 NA      13.37872      -70.42856    -84.85306
## 6                 NA      13.38246      -70.81759    -84.46500
## 7                 NA      13.12695      -70.24757    -85.09961
## 8                 NA      12.75083      -70.34768    -85.09708
## 9                 NA      13.15463      -70.42520    -84.91563
## 10                NA      13.33034      -70.85059    -84.44602
##    kurtosis_roll_dumbbell kurtosis_picth_dumbbell kurtosis_yaw_dumbbell
## 1                      NA                      NA                    NA
## 2                      NA                      NA                    NA
## 3                      NA                      NA                    NA
## 4                      NA                      NA                    NA
## 5                      NA                      NA                    NA
## 6                      NA                      NA                    NA
## 7                      NA                      NA                    NA
## 8                      NA                      NA                    NA
## 9                      NA                      NA                    NA
## 10                     NA                      NA                    NA
##    skewness_roll_dumbbell skewness_pitch_dumbbell skewness_yaw_dumbbell
## 1                      NA                      NA                    NA
## 2                      NA                      NA                    NA
## 3                      NA                      NA                    NA
## 4                      NA                      NA                    NA
## 5                      NA                      NA                    NA
## 6                      NA                      NA                    NA
## 7                      NA                      NA                    NA
## 8                      NA                      NA                    NA
## 9                      NA                      NA                    NA
## 10                     NA                      NA                    NA
##    max_roll_dumbbell max_picth_dumbbell max_yaw_dumbbell min_roll_dumbbell
## 1                 NA                 NA               NA                NA
## 2                 NA                 NA               NA                NA
## 3                 NA                 NA               NA                NA
## 4                 NA                 NA               NA                NA
## 5                 NA                 NA               NA                NA
## 6                 NA                 NA               NA                NA
## 7                 NA                 NA               NA                NA
## 8                 NA                 NA               NA                NA
## 9                 NA                 NA               NA                NA
## 10                NA                 NA               NA                NA
##    min_pitch_dumbbell min_yaw_dumbbell amplitude_roll_dumbbell
## 1                  NA               NA                      NA
## 2                  NA               NA                      NA
## 3                  NA               NA                      NA
## 4                  NA               NA                      NA
## 5                  NA               NA                      NA
## 6                  NA               NA                      NA
## 7                  NA               NA                      NA
## 8                  NA               NA                      NA
## 9                  NA               NA                      NA
## 10                 NA               NA                      NA
##    amplitude_pitch_dumbbell amplitude_yaw_dumbbell total_accel_dumbbell
## 1                        NA                     NA                   37
## 2                        NA                     NA                   37
## 3                        NA                     NA                   37
## 4                        NA                     NA                   37
## 5                        NA                     NA                   37
## 6                        NA                     NA                   37
## 7                        NA                     NA                   37
## 8                        NA                     NA                   37
## 9                        NA                     NA                   37
## 10                       NA                     NA                   37
##    var_accel_dumbbell avg_roll_dumbbell stddev_roll_dumbbell var_roll_dumbbell
## 1                  NA                NA                   NA                NA
## 2                  NA                NA                   NA                NA
## 3                  NA                NA                   NA                NA
## 4                  NA                NA                   NA                NA
## 5                  NA                NA                   NA                NA
## 6                  NA                NA                   NA                NA
## 7                  NA                NA                   NA                NA
## 8                  NA                NA                   NA                NA
## 9                  NA                NA                   NA                NA
## 10                 NA                NA                   NA                NA
##    avg_pitch_dumbbell stddev_pitch_dumbbell var_pitch_dumbbell avg_yaw_dumbbell
## 1                  NA                    NA                 NA               NA
## 2                  NA                    NA                 NA               NA
## 3                  NA                    NA                 NA               NA
## 4                  NA                    NA                 NA               NA
## 5                  NA                    NA                 NA               NA
## 6                  NA                    NA                 NA               NA
## 7                  NA                    NA                 NA               NA
## 8                  NA                    NA                 NA               NA
## 9                  NA                    NA                 NA               NA
## 10                 NA                    NA                 NA               NA
##    stddev_yaw_dumbbell var_yaw_dumbbell gyros_dumbbell_x gyros_dumbbell_y
## 1                   NA               NA                0            -0.02
## 2                   NA               NA                0            -0.02
## 3                   NA               NA                0            -0.02
## 4                   NA               NA                0            -0.02
## 5                   NA               NA                0            -0.02
## 6                   NA               NA                0            -0.02
## 7                   NA               NA                0            -0.02
## 8                   NA               NA                0            -0.02
## 9                   NA               NA                0            -0.02
## 10                  NA               NA                0            -0.02
##    gyros_dumbbell_z accel_dumbbell_x accel_dumbbell_y accel_dumbbell_z
## 1              0.00             -234               47             -271
## 2              0.00             -233               47             -269
## 3              0.00             -232               46             -270
## 4             -0.02             -232               48             -269
## 5              0.00             -233               48             -270
## 6              0.00             -234               48             -269
## 7              0.00             -232               47             -270
## 8              0.00             -234               46             -272
## 9              0.00             -232               47             -269
## 10             0.00             -235               48             -270
##    magnet_dumbbell_x magnet_dumbbell_y magnet_dumbbell_z roll_forearm
## 1               -559               293               -65         28.4
## 2               -555               296               -64         28.3
## 3               -561               298               -63         28.3
## 4               -552               303               -60         28.1
## 5               -554               292               -68         28.0
## 6               -558               294               -66         27.9
## 7               -551               295               -70         27.9
## 8               -555               300               -74         27.8
## 9               -549               292               -65         27.7
## 10              -558               291               -69         27.7
##    pitch_forearm yaw_forearm kurtosis_roll_forearm kurtosis_picth_forearm
## 1          -63.9        -153                    NA                     NA
## 2          -63.9        -153                    NA                     NA
## 3          -63.9        -152                    NA                     NA
## 4          -63.9        -152                    NA                     NA
## 5          -63.9        -152                    NA                     NA
## 6          -63.9        -152                    NA                     NA
## 7          -63.9        -152                    NA                     NA
## 8          -63.8        -152                    NA                     NA
## 9          -63.8        -152                    NA                     NA
## 10         -63.8        -152                    NA                     NA
##    kurtosis_yaw_forearm skewness_roll_forearm skewness_pitch_forearm
## 1                    NA                    NA                     NA
## 2                    NA                    NA                     NA
## 3                    NA                    NA                     NA
## 4                    NA                    NA                     NA
## 5                    NA                    NA                     NA
## 6                    NA                    NA                     NA
## 7                    NA                    NA                     NA
## 8                    NA                    NA                     NA
## 9                    NA                    NA                     NA
## 10                   NA                    NA                     NA
##    skewness_yaw_forearm max_roll_forearm max_picth_forearm max_yaw_forearm
## 1                    NA               NA                NA              NA
## 2                    NA               NA                NA              NA
## 3                    NA               NA                NA              NA
## 4                    NA               NA                NA              NA
## 5                    NA               NA                NA              NA
## 6                    NA               NA                NA              NA
## 7                    NA               NA                NA              NA
## 8                    NA               NA                NA              NA
## 9                    NA               NA                NA              NA
## 10                   NA               NA                NA              NA
##    min_roll_forearm min_pitch_forearm min_yaw_forearm amplitude_roll_forearm
## 1                NA                NA              NA                     NA
## 2                NA                NA              NA                     NA
## 3                NA                NA              NA                     NA
## 4                NA                NA              NA                     NA
## 5                NA                NA              NA                     NA
## 6                NA                NA              NA                     NA
## 7                NA                NA              NA                     NA
## 8                NA                NA              NA                     NA
## 9                NA                NA              NA                     NA
## 10               NA                NA              NA                     NA
##    amplitude_pitch_forearm amplitude_yaw_forearm total_accel_forearm
## 1                       NA                    NA                  36
## 2                       NA                    NA                  36
## 3                       NA                    NA                  36
## 4                       NA                    NA                  36
## 5                       NA                    NA                  36
## 6                       NA                    NA                  36
## 7                       NA                    NA                  36
## 8                       NA                    NA                  36
## 9                       NA                    NA                  36
## 10                      NA                    NA                  36
##    var_accel_forearm avg_roll_forearm stddev_roll_forearm var_roll_forearm
## 1                 NA               NA                  NA               NA
## 2                 NA               NA                  NA               NA
## 3                 NA               NA                  NA               NA
## 4                 NA               NA                  NA               NA
## 5                 NA               NA                  NA               NA
## 6                 NA               NA                  NA               NA
## 7                 NA               NA                  NA               NA
## 8                 NA               NA                  NA               NA
## 9                 NA               NA                  NA               NA
## 10                NA               NA                  NA               NA
##    avg_pitch_forearm stddev_pitch_forearm var_pitch_forearm avg_yaw_forearm
## 1                 NA                   NA                NA              NA
## 2                 NA                   NA                NA              NA
## 3                 NA                   NA                NA              NA
## 4                 NA                   NA                NA              NA
## 5                 NA                   NA                NA              NA
## 6                 NA                   NA                NA              NA
## 7                 NA                   NA                NA              NA
## 8                 NA                   NA                NA              NA
## 9                 NA                   NA                NA              NA
## 10                NA                   NA                NA              NA
##    stddev_yaw_forearm var_yaw_forearm gyros_forearm_x gyros_forearm_y
## 1                  NA              NA            0.03            0.00
## 2                  NA              NA            0.02            0.00
## 3                  NA              NA            0.03           -0.02
## 4                  NA              NA            0.02           -0.02
## 5                  NA              NA            0.02            0.00
## 6                  NA              NA            0.02           -0.02
## 7                  NA              NA            0.02            0.00
## 8                  NA              NA            0.02           -0.02
## 9                  NA              NA            0.03            0.00
## 10                 NA              NA            0.02            0.00
##    gyros_forearm_z accel_forearm_x accel_forearm_y accel_forearm_z
## 1            -0.02             192             203            -215
## 2            -0.02             192             203            -216
## 3             0.00             196             204            -213
## 4             0.00             189             206            -214
## 5            -0.02             189             206            -214
## 6            -0.03             193             203            -215
## 7            -0.02             195             205            -215
## 8             0.00             193             205            -213
## 9            -0.02             193             204            -214
## 10           -0.02             190             205            -215
##    magnet_forearm_x magnet_forearm_y magnet_forearm_z classe
## 1               -17              654              476      A
## 2               -18              661              473      A
## 3               -18              658              469      A
## 4               -16              658              469      A
## 5               -17              655              473      A
## 6                -9              660              478      A
## 7               -18              659              470      A
## 8                -9              660              474      A
## 9               -16              653              476      A
## 10              -22              656              473      A

Note that the echo = FALSE parameter was added to the code chunk to prevent printing of the R code.

Cross-Validation

It is decided to use 60/40 separation between the training and testing datasets Since testing dataset is too small - we will create a new testing dataset from partitioning the training dataset that has sufficient number of observations

# loading the packages
install_and_load = function(name, char = T)
{
  if (!require(name, character.only = char)) 
  {
    install.packages(name)
  }
  require(name, character.only = char)
}
sapply(
  c("caret","randomForest","magrittr", "tidyr", "rattle"),
  install_and_load
)
##        caret randomForest     magrittr        tidyr       rattle 
##         TRUE         TRUE         TRUE         TRUE         TRUE
rm(install_and_load)

# Training dataset (60%); Testing dataset (40%) 
set.seed(13082020)
inTrain = caret::createDataPartition(y=training$classe,p=0.6, list=FALSE)
# training dataset - select rows
training_set = training[inTrain,]
# testing dataset - select remaining rows
testing_set = training[-inTrain,]

Data cleaning

Near zero covariates and the data containing too many NAs or NANs or Inf or -Inf should be removed from the DS.

# Removing near zero covariates
my_near_zero_vars = nearZeroVar(x = training, saveMetrics = TRUE)
# View(my_near_zero_vars) #DF of covariates and if they are NZV

# Removing covariates with more than 40% NA values
my_NA_values = !as.logical(apply(training, 2, function(x){ mean(is.na(x)) >= 0.4}))
# View(my_NA_values) # Returns TRUE/FALSE DF for each column if NAs are above SET percent.

# Cleaning data
my_indicator_up_2 = my_NA_values*1 + (!my_near_zero_vars$nzv)*1
# View(my_indicator_up_2) #Returns DF with 0, 1 or 2 for each column;
# 2 means we have NAs below the threshold and not NZV covariate
my_indicator_up_2_equal_2 = my_indicator_up_2 == 2
# View(my_indicator_up_2_equal_2) # Now we have a list of all indicators equal to 2 TRUE/FALSE for each column
sum(my_indicator_up_2_equal_2)
## [1] 59
# Shows the number of usefulcovariates (columns)

#View(data.frame(my_NA_values, !my_near_zero_vars$nzv, my_indicator_up_2, my_indicator_up_2_equal_2))

training_set = training_set[,my_indicator_up_2_equal_2] #View(training_set) #OK variables left
testing_set = testing_set[, my_indicator_up_2_equal_2]

# The X colymn (the first column) is something like a database key - remove it:
training_set = training_set[, -1] #Now it is a colum row.names
testing_set = testing_set[, -1]
# Same operations with the primary testing datatset
testing = testing[,my_indicator_up_2_equal_2]
testing = testing[,-1]

# This loop is inspired by the Coursera courses and additional searching
# We had the testing DF uploaded from http - it has about 20 observations
# Coerce the data into the same type in order to avoid the "Matching Error" when calling random forest model, due to different levels in variables
# This loop helps to apply the model MLT to any further DS without the mentioned error
for (i in 1:length(testing) ) {
  for(j in 1:length(training_set)) {
    if( length( grep(names(training_set[i]), names(testing)[j]) ) == 1)  {
      class(testing[j]) <- class(training_set[i])
    }      
  }      
}

# To get the same class between testing and training_set
testing = testing[,-ncol(testing)]
testing <- rbind(training_set[2, -58] , testing) #It adds additional observation (row) - we may see if it is added correctly
testing <- testing[-1,]

#Now the DS is ready for work

RPART method prediction with decision trees

# Build model
set.seed(13082020)
# training_set[,-ncol(training_set)] #Means without the shadow column row.names generated by R automatically. dim(training_set) [1] 11776    58 dim(training_set[,-ncol(training_set)]) [1] 11776    57


my_tree = train(y = training_set$classe,
                 x = training_set[,-ncol(training_set)],
                 method = "rpart")

# Plot classification tree
rattle::fancyRpartPlot(
  my_tree$finalModel
)

# Predictions with rpart model
prediction_from_tree = predict(my_tree, testing_set[,-ncol(testing_set)])
prediction_from_tree = predict(my_tree, testing_set)
# View(prediction_from_tree)
# View(testing_set$classe)
str(prediction_from_tree) #Factor
##  Factor w/ 5 levels "A","B","C","D",..: 1 1 1 1 1 1 1 1 1 1 ...
str(testing_set$classe) #Character - will cause error in confusion matrix
##  chr [1:7846] "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" ...
# solution:
reality_without_trees = as.factor(testing_set$classe)
str(reality_without_trees)
##  Factor w/ 5 levels "A","B","C","D",..: 1 1 1 1 1 1 1 1 1 1 ...
# Get results (Accuracy, etc.)
# confusionMatrix(prediction_from_tree, testing_set$classe)

confusionMatrix(prediction_from_tree, reality_without_trees)
## Confusion Matrix and Statistics
## 
##           Reference
## Prediction    A    B    C    D    E
##          A 1438  128    0    0    0
##          B  794 1374 1017  237    0
##          C    0    0    0    0    0
##          D    0    0    0    0    0
##          E    0   16  351 1049 1442
## 
## Overall Statistics
##                                           
##                Accuracy : 0.5422          
##                  95% CI : (0.5311, 0.5533)
##     No Information Rate : 0.2845          
##     P-Value [Acc > NIR] : < 2.2e-16       
##                                           
##                   Kappa : 0.4219          
##                                           
##  Mcnemar's Test P-Value : NA              
## 
## Statistics by Class:
## 
##                      Class: A Class: B Class: C Class: D Class: E
## Sensitivity            0.6443   0.9051   0.0000   0.0000   1.0000
## Specificity            0.9772   0.6764   1.0000   1.0000   0.7789
## Pos Pred Value         0.9183   0.4015      NaN      NaN   0.5045
## Neg Pred Value         0.8736   0.9675   0.8256   0.8361   1.0000
## Prevalence             0.2845   0.1935   0.1744   0.1639   0.1838
## Detection Rate         0.1833   0.1751   0.0000   0.0000   0.1838
## Detection Prevalence   0.1996   0.4361   0.0000   0.0000   0.3643
## Balanced Accuracy      0.8107   0.7907   0.5000   0.5000   0.8894
# Accuracy is 55% which is OK for micro-data

RPART method prediction with Random Forest

# Prediction with Random Forest
# Build model
set.seed(13082020)
str(testing_set$classe) #Character - will cause error in Random forest (from documentation)
##  chr [1:7846] "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" "A" ...
testing_set$classe <- factor(testing_set$classe) 
str(testing_set$classe)
##  Factor w/ 5 levels "A","B","C","D",..: 1 1 1 1 1 1 1 1 1 1 ...
training_set$classe <- factor(training_set$classe) 
str(training_set$classe)
##  Factor w/ 5 levels "A","B","C","D",..: 1 1 1 1 1 1 1 1 1 1 ...
my_random_forest_model = randomForest(
  classe ~ .,
  data = training_set,
  ntree = 150) #No need to overload system with higher Ntrees

# Plot the Random Forests model
plot(my_random_forest_model) #Chart reveals - no urgent need to plant more trees than we have already planted

# Predict with random forest model
RF_prediction = predict(
  my_random_forest_model,
  testing_set[,-ncol(testing_set)]
)

# Get results (Accuracy, etc.)
confusionMatrix(RF_prediction, testing_set$classe)
## Confusion Matrix and Statistics
## 
##           Reference
## Prediction    A    B    C    D    E
##          A 2232    1    0    0    0
##          B    0 1516    0    0    0
##          C    0    1 1365   10    0
##          D    0    0    3 1276    2
##          E    0    0    0    0 1440
## 
## Overall Statistics
##                                           
##                Accuracy : 0.9978          
##                  95% CI : (0.9965, 0.9987)
##     No Information Rate : 0.2845          
##     P-Value [Acc > NIR] : < 2.2e-16       
##                                           
##                   Kappa : 0.9973          
##                                           
##  Mcnemar's Test P-Value : NA              
## 
## Statistics by Class:
## 
##                      Class: A Class: B Class: C Class: D Class: E
## Sensitivity            1.0000   0.9987   0.9978   0.9922   0.9986
## Specificity            0.9998   1.0000   0.9983   0.9992   1.0000
## Pos Pred Value         0.9996   1.0000   0.9920   0.9961   1.0000
## Neg Pred Value         1.0000   0.9997   0.9995   0.9985   0.9997
## Prevalence             0.2845   0.1935   0.1744   0.1639   0.1838
## Detection Rate         0.2845   0.1932   0.1740   0.1626   0.1835
## Detection Prevalence   0.2846   0.1932   0.1754   0.1633   0.1835
## Balanced Accuracy      0.9999   0.9993   0.9981   0.9957   0.9993
# Acuracy is almost 100% - it is even better

First conclusion

Random forest mode has accuracy level at almost 100% - it is even better than our decision trees model we used as well.

Using our model to predict the testing dataset

# Get predictions for the 20 observations of the original pml-testing.csv

my_prediction = predict(my_random_forest_model, testing)
my_prediction
##  1 21  3  4  5  6  7  8  9 10 11 12 13 14 15 16 17 18 19 20 
##  B  A  B  A  A  E  D  B  A  A  B  C  B  A  E  E  A  B  B  B 
## Levels: A B C D E
summary(my_prediction)
## A B C D E 
## 7 8 1 1 3

Last action: saving the results

# Saving predictions for testing dataset
testing$predicted_classe = my_prediction

write.table(
  testing,
  file = "C:/Users/Alex/Documents/COURSERA STUDIES/Practical Machine Learning/Final_Project/testing_and_predictions",
  quote = F
)

Thank you