1. Consider the following 20 samples drawn from a population:

24.7 23.5 14.7 13.4 24.2 25.4 12.1 15.0 19.6 22.9 21.2 18.4 25.0 14.5 14.2 21.8 21.2 15.7 22.6 21.2

  1. Calculate the sample mean
df<-c(24.7,23.5,14.7,13.4,24.2,25.4, 12.1,15.0,19.6,22.9,21.2,18.4,25.0, 14.5,14.2,21.8,21.2,15.7,22.6,21.2)

mean(df)
## [1] 19.565
  1. Calculate the median
median(df)
## [1] 21.2
  1. Calculate the sample variance
sd(df)^2
## [1] 19.43397
  1. Calculate the sample standard deviation
sd(df)
## [1] 4.408398
  1. Calculate the quartiles
quantile(df)
##     0%    25%    50%    75%   100% 
## 12.100 14.925 21.200 23.050 25.400
  1. Draw a histogram with 4 bins (change both the fill and border color)
hist(df,breaks = 4,col = "yellow", border = "blue")

  1. Draw a boxplot
boxplot(df)

  1. Consider a random sample of n=50 resistors from suppliers A and B contained in the datafile

https://raw.githubusercontent.com/tmatis12/datafiles/main/resistors.csv

df2<-read.csv("https://raw.githubusercontent.com/tmatis12/datafiles/main/resistors.csv")

head(df2)
##   SupplierA SupplierB
## 1  29.36279  30.62987
## 2  29.51027  29.13114
## 3  29.92811  29.81491
## 4  29.78606  29.46583
## 5  29.15107  29.59829
## 6  30.15748  29.12295
  1. Calculate a summary (min, max, quartiles, mean, median) of the descriptive statistics for Supplier A (using the summary() command)
summary(df2$SupplierA)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   28.71   29.52   29.89   29.92   30.28   31.44
  1. Calculate a histogram of the sample from supplier A (create a unique title and axes label). Does the data “look” Normally distributed?
hist(df2$SupplierA, main = "Histogram of Supplier A", xlab="xlabel", ylabel="frecuency")
## Warning in plot.window(xlim, ylim, "", ...): "ylabel" is not a graphical
## parameter
## Warning in title(main = main, sub = sub, xlab = xlab, ylab = ylab, ...):
## "ylabel" is not a graphical parameter
## Warning in axis(1, ...): "ylabel" is not a graphical parameter
## Warning in axis(2, at = yt, ...): "ylabel" is not a graphical parameter

The data looks kind of Normally distributed with that number of bins due to the bell shape and peak at x = 30. c) Calculate side by side box plot

boxplot(df2)

  1. Consider a sample of body temperature and heartbeat for n=65 males (1) and females (2) contained in the datafile

https://raw.githubusercontent.com/tmatis12/datafiles/main/normtemp.csv

df3 <- read.csv("https://raw.githubusercontent.com/tmatis12/datafiles/main/normtemp.csv")

df3
##      Temp Sex Beats
## 1    96.3   1    70
## 2    96.7   1    71
## 3    96.9   1    74
## 4    97.0   1    80
## 5    97.1   1    73
## 6    97.1   1    75
## 7    97.1   1    82
## 8    97.2   1    64
## 9    97.3   1    69
## 10   97.4   1    70
## 11   97.4   1    68
## 12   97.4   1    72
## 13   97.4   1    78
## 14   97.5   1    70
## 15   97.5   1    75
## 16   97.6   1    74
## 17   97.6   1    69
## 18   97.6   1    73
## 19   97.7   1    77
## 20   97.8   1    58
## 21   97.8   1    73
## 22   97.8   1    65
## 23   97.8   1    74
## 24   97.9   1    76
## 25   97.9   1    72
## 26   98.0   1    78
## 27   98.0   1    71
## 28   98.0   1    74
## 29   98.0   1    67
## 30   98.0   1    64
## 31   98.0   1    78
## 32   98.1   1    73
## 33   98.1   1    67
## 34   98.2   1    66
## 35   98.2   1    64
## 36   98.2   1    71
## 37   98.2   1    72
## 38   98.3   1    86
## 39   98.3   1    72
## 40   98.4   1    68
## 41   98.4   1    70
## 42   98.4   1    82
## 43   98.4   1    84
## 44   98.5   1    68
## 45   98.5   1    71
## 46   98.6   1    77
## 47   98.6   1    78
## 48   98.6   1    83
## 49   98.6   1    66
## 50   98.6   1    70
## 51   98.6   1    82
## 52   98.7   1    73
## 53   98.7   1    78
## 54   98.8   1    78
## 55   98.8   1    81
## 56   98.8   1    78
## 57   98.9   1    80
## 58   99.0   1    75
## 59   99.0   1    79
## 60   99.0   1    81
## 61   99.1   1    71
## 62   99.2   1    83
## 63   99.3   1    63
## 64   99.4   1    70
## 65   99.5   1    75
## 66   96.4   2    69
## 67   96.7   2    62
## 68   96.8   2    75
## 69   97.2   2    66
## 70   97.2   2    68
## 71   97.4   2    57
## 72   97.6   2    61
## 73   97.7   2    84
## 74   97.7   2    61
## 75   97.8   2    77
## 76   97.8   2    62
## 77   97.8   2    71
## 78   97.9   2    68
## 79   97.9   2    69
## 80   97.9   2    79
## 81   98.0   2    76
## 82   98.0   2    87
## 83   98.0   2    78
## 84   98.0   2    73
## 85   98.0   2    89
## 86   98.1   2    81
## 87   98.2   2    73
## 88   98.2   2    64
## 89   98.2   2    65
## 90   98.2   2    73
## 91   98.2   2    69
## 92   98.2   2    57
## 93   98.3   2    79
## 94   98.3   2    78
## 95   98.3   2    80
## 96   98.4   2    79
## 97   98.4   2    81
## 98   98.4   2    73
## 99   98.4   2    74
## 100  98.4   2    84
## 101  98.5   2    83
## 102  98.6   2    82
## 103  98.6   2    85
## 104  98.6   2    86
## 105  98.6   2    77
## 106  98.7   2    72
## 107  98.7   2    79
## 108  98.7   2    59
## 109  98.7   2    64
## 110  98.7   2    65
## 111  98.7   2    82
## 112  98.8   2    64
## 113  98.8   2    70
## 114  98.8   2    83
## 115  98.8   2    89
## 116  98.8   2    69
## 117  98.8   2    73
## 118  98.8   2    84
## 119  98.9   2    76
## 120  99.0   2    79
## 121  99.0   2    81
## 122  99.1   2    80
## 123  99.1   2    74
## 124  99.2   2    77
## 125  99.2   2    66
## 126  99.3   2    68
## 127  99.4   2    77
## 128  99.9   2    79
## 129 100.0   2    78
## 130 100.8   2    77
  1. Calculate a summary of the descriptive statistics of heartbeat and body temperature for both males and females.
summary(df3$Temp)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   96.30   97.80   98.30   98.25   98.70  100.80
summary(df3$Beats)
##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##   57.00   69.00   74.00   73.76   79.00   89.00
  1. Calculate a histogram of heartbeat for females (create a unique title and axes label, change the color to pink).
fem<-df3[df3$Sex==2,]
fem
##      Temp Sex Beats
## 66   96.4   2    69
## 67   96.7   2    62
## 68   96.8   2    75
## 69   97.2   2    66
## 70   97.2   2    68
## 71   97.4   2    57
## 72   97.6   2    61
## 73   97.7   2    84
## 74   97.7   2    61
## 75   97.8   2    77
## 76   97.8   2    62
## 77   97.8   2    71
## 78   97.9   2    68
## 79   97.9   2    69
## 80   97.9   2    79
## 81   98.0   2    76
## 82   98.0   2    87
## 83   98.0   2    78
## 84   98.0   2    73
## 85   98.0   2    89
## 86   98.1   2    81
## 87   98.2   2    73
## 88   98.2   2    64
## 89   98.2   2    65
## 90   98.2   2    73
## 91   98.2   2    69
## 92   98.2   2    57
## 93   98.3   2    79
## 94   98.3   2    78
## 95   98.3   2    80
## 96   98.4   2    79
## 97   98.4   2    81
## 98   98.4   2    73
## 99   98.4   2    74
## 100  98.4   2    84
## 101  98.5   2    83
## 102  98.6   2    82
## 103  98.6   2    85
## 104  98.6   2    86
## 105  98.6   2    77
## 106  98.7   2    72
## 107  98.7   2    79
## 108  98.7   2    59
## 109  98.7   2    64
## 110  98.7   2    65
## 111  98.7   2    82
## 112  98.8   2    64
## 113  98.8   2    70
## 114  98.8   2    83
## 115  98.8   2    89
## 116  98.8   2    69
## 117  98.8   2    73
## 118  98.8   2    84
## 119  98.9   2    76
## 120  99.0   2    79
## 121  99.0   2    81
## 122  99.1   2    80
## 123  99.1   2    74
## 124  99.2   2    77
## 125  99.2   2    66
## 126  99.3   2    68
## 127  99.4   2    77
## 128  99.9   2    79
## 129 100.0   2    78
## 130 100.8   2    77
hist(fem$Beats,main = "Histogram of Female Heartbeats", xlab = "Number of beats", ylab="Frecuency", col = "pink")

  1. Calculate a histogram of heartbeat for males (create a unique title and axes label, change the color to blue).
mal<-df3[df3$Sex==1,]
hist(mal$Beats,main = "Histogram of Male Heartbeats", xlab = "Number of beats", ylab="Frecuency", col = "blue")

  1. Across both males and females, what is the sample correlation coefficient between heartbeat and body temperature?
cor(df3$Temp,df3$Beats)
## [1] 0.2536564