# PS2.2 -- on means, s.d., c.v., Section 2.2
open data2-2 
summary colgpa 
# learn about the summary command 
help summary 
# verify summary statistics by computing them separately 
genr xbar=mean(colgpa)
# s.d. of colgpa 			
genr sdx=sd(colgpa)
# variance of colgpa 		
genr varx = sdx*sdx
# coefficient of variation 		
genr cv = sdx/xbar
# list the variables                 
list
# reset sample range 		
smpl 1 1 
# print variables 			
print xbar varx sdx cv 
