User Guide

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Chapter 11
More about Comparing M eans
The following examples suggest some ways in which you can use other procedures to
compare means.
 Independent-Samples T Test. When you use a t test to compare means of one
variable across independent groups, the samples are independent. Males and
females in t
he demo.sav file can be divided into independent groups by the
variable Gender (gender).Youcanuseat test to determine if the mean household
incomes of males and females are the same.
 One-Sample T Test. You can test whether the household income of people with
college de
grees differs from a national or state average. Use
Select Cases on the
Data menu to select the cases with LevelofEducation(ed)>= 4. Then, run
the One-Sample T Test procedure to compare Household income in thousands
(income)
and the test value 75.
 One-Way A
NOVA.
The variable Level of Education (ed) divides employees into five
independent groups by level of education. You can use the One-Way ANOVA
procedure to test whether Household income in thousands (income) means for the
five grou
ps are significantly different.
ANOVA Models
The General Linear Model submenu on the Analyze menu provides techniques for
testing
univariate analysis-of-variance models. (If you have only one factor, you can
use the One-Way ANOVA procedure on the Compare Means submenu.)
Univari
ate Analysis of Variance
The GLM U
nivariate procedure can perform an analysis of variance for factorial
designs. A simple factorial design can be used to test if a person’s household income
and job satisfaction affect the number of years with current employer.