Confidence intervals for means

Written by:

Ylva B Almquist

Introduction

Confidence intervals for means can be calculated for continuous variables with a normal distribution. 

Function

Basic command
ci means varlist 
Useful options
ci means varlist, level(#) 
Explanations
varlistInsert the name(s) of the variable(s) that you want to use. 
level(#)Specify the confidence level. Default is 95.
More information
help ci

Practical example

Dataset
StataData1.dta
Variable namegpa
Variable labelGrade point average (Age 15, Year 1985)
Value labelsN/A
ci means gpa

In this example, we can see that the mean value for gpa is 3.18. The 95% confidence interval is 3.16-3.19.