#scripts & functions for STAT 221
 source("http://www.uvm.edu/~rsingle/stat5210/data/scripts-5210.R")

 z500 <- rnorm(500)
 x500 <- rchisq(500,3)
 t500 <- rt(500,3)
 u500 <- runif(500, -1,1)

#Skewness & Kurtosis 
 skewness(z500)
 kurtosis(z500)
 
 skewness(x500)
 kurtosis(x500)

 skewness(t500)
 kurtosis(t500)
 
#Boxplots
 boxplot(z500)
 title("boxplot of z500")
 boxplot(z500, main="z500")
 
 boxplot(x500, main="x500")
 boxplot(t500, main="t500")
 boxplot(u500, main="u500")
 
multifig(2,2)  #plot 4 items on one page
 boxplot(z500, main="z500")
 boxplot(x500, main="x500")
 boxplot(t500, main="t500")
 boxplot(u500, main="u500")
multifig(1,1)  #revert to one item per page

#Q-Q plots
 qqnorm(z500, main="normal" ); qqline(z500)
 qqnorm(x500, main="chisq"  ); qqline(x500)
 qqnorm(t500, main="t-dist" ); qqline(t500)
 qqnorm(u500, main="uniform"); qqline(u500)

#histograms
 hist(z500, main="normal" )
 hist(x500, main="chisq"  )
 hist(t500, main="t-dist" )
 hist(u500, main="uniform")