Using data from accelerometers, we predict the manner in which individuals perform weightlifting exercises. The target variable is classe, which indicates the correctness of the exercise execution.
library(caret)## Loading required package: ggplot2## Loading required package: latticelibrary(randomForest)## randomForest 4.6-14## Type rfNews() to see new features/changes/bug fixes.##
## Attaching package: 'randomForest'## The following object is masked from 'package:ggplot2':
##
## marginlibrary(ggplot2)
library(dplyr)##
## Attaching package: 'dplyr'## The following object is masked from 'package:randomForest':
##
## combine## The following objects are masked from 'package:stats':
##
## filter, lag## The following objects are masked from 'package:base':
##
## intersect, setdiff, setequal, uniontrain_url <- "https://d396qusza40orc.cloudfront.net/predmachlearn/pml-training.csv"
test_url <- "https://d396qusza40orc.cloudfront.net/predmachlearn/pml-testing.csv"
train_data <- read.csv(train_url, na.strings = c("NA", "", "#DIV/0!"))
test_data <- read.csv(test_url, na.strings = c("NA", "", "#DIV/0!"))
str(train_data)## '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]summary(train_data)## 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
##
##
##
## # Remove columns with many missing values
train_data <- train_data[, colSums(is.na(train_data)) == 0]
# Remove irrelevant columns (ID, timestamps, etc.)
train_data <- train_data %>% select(-c(1:7))
# Convert classe to factor
train_data$classe <- as.factor(train_data$classe)set.seed(123)
trainIndex <- createDataPartition(train_data$classe, p = 0.8, list = FALSE)
train_set <- train_data[trainIndex, ]
valid_set <- train_data[-trainIndex, ]set.seed(123)
rf_model <- randomForest(classe ~ ., data = train_set, ntree = 100)pred_valid <- predict(rf_model, valid_set)
conf_matrix <- confusionMatrix(pred_valid, valid_set$classe)
conf_matrix## Confusion Matrix and Statistics
##
## Reference
## Prediction A B C D E
## A 1116 4 0 0 0
## B 0 755 2 0 0
## C 0 0 682 4 0
## D 0 0 0 639 5
## E 0 0 0 0 716
##
## Overall Statistics
##
## Accuracy : 0.9962
## 95% CI : (0.9937, 0.9979)
## No Information Rate : 0.2845
## P-Value [Acc > NIR] : < 2.2e-16
##
## Kappa : 0.9952
##
## Mcnemar's Test P-Value : NA
##
## Statistics by Class:
##
## Class: A Class: B Class: C Class: D Class: E
## Sensitivity 1.0000 0.9947 0.9971 0.9938 0.9931
## Specificity 0.9986 0.9994 0.9988 0.9985 1.0000
## Pos Pred Value 0.9964 0.9974 0.9942 0.9922 1.0000
## Neg Pred Value 1.0000 0.9987 0.9994 0.9988 0.9984
## Prevalence 0.2845 0.1935 0.1744 0.1639 0.1838
## Detection Rate 0.2845 0.1925 0.1738 0.1629 0.1825
## Detection Prevalence 0.2855 0.1930 0.1749 0.1642 0.1825
## Balanced Accuracy 0.9993 0.9970 0.9979 0.9961 0.9965test_data <- test_data[, colnames(test_data) %in% colnames(train_set)]
test_predictions <- predict(rf_model, test_data)
test_predictions## 1 2 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