10.1 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