4.1 Basic Statistics

Central Tendency

x <- 1:40
mean(x)   

## [1] 20.5

median(x)

## [1] 20.5

summary(x)  #Five-number summary

##    Min. 1st Qu.  Median    Mean 3rd Qu.    Max. 
##    1.00   10.75   20.50   20.50   30.25   40.00

Dispersion

range(x)     #Get minimum and maximum

## [1]  1 40

IQR(x)       #Inter-quartile range

## [1] 19.5

var(x)       #variance

## [1] 136.6667

sd(x)        #Standard deviation

## [1] 11.69045