I choose AGE variable and prepare SPSS syntax and output:
Syntax:
GET FILE='D:\SPSS+ 'SPSS\gss04student_corrrected.sav'. >Warning. Command name: GET FILE >SPSS Statistics system file "D:\SPSS\gss04student_corrrected.sav" is written in a character encoding (windows-1252) >incompatible with the current LOCALE setting. It may not be readable. >Consider changing LOCALE or setting UNICODE on. (DATA 1721) EXAMINE VARIABLES=AGE /PLOT BOXPLOT HISTOGRAM NPPLOT /COMPARE GROUP /STATISTICS DESCRIPTIVES /CINTERVAL 95 /MISSING LISTWISE /NOTOTAL.
Now it’s time for hypothesis testing. I choose nominal variable “SEX” and want to check the claim that there is a great difference in average age between men and women. So, state the hypothesis:
H0: μ1=μ2
Ha: μ1≠μ2
Set the level of significance alpha = 0.05
Now perform independent sample t-test (two-tailed), using SPSS:
Since p-value of the test is 0.442, we can’t reject the null hypothesis. We have no evidence to say about the significant difference in age between men and women (at the given level of significance 5%). The age is approximately equal (on average).
References
Argyrous, G. Statistics for Research: With a Guide to SPSS, SAGE, London, ISBN 1-4129-1948-7
Levesque, R. SPSS Programming and Data Management: A Guide for SPSS and SAS Users, Fourth Edition (2007), SPSS Inc., Chicago Ill. ISBN 1-56827-390-8
SPSS 15.0 Command Syntax Reference 2006, SPSS Inc., Chicago Ill.
Wellman, B. "Doing It Ourselves: The SPSS Manual as Sociology's Most Influential Recent Book." pp. 71–78 in Required Reading: Sociology's Most Influential Books, edited by Dan Clawson. Amherst: University of Massachusetts Press, 1998. ISBN 978-1-55849-153-3
