Hello, I am running a basic Ttest to estimate gender (varX) differences in income (varY). However, I want to segregate the analysis by 3 separate racial groups.
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At the moment, Ttest only supports 1 variable on the groups command. A longer way is to limit the analysis to each group (using select cases), and run the Ttest repeatedly/separately. Is there a different way to accomplish this in SPSS? thanks, CY 
Another way to get 3 ttests is to sort the file and use SPLIT FILE  you might prefer the layout this way.
A ttest is an alternate computation for the oneway ANOVA, applicable when there are just two groups. The square
of the ttest value is equal to the corresponding Ftest. If you do a 3x2 ANOVA, you get the overall comparison for your varX (gender); if you work for it, you could also get contrasts using the common denominator for tests.
 Rich Ulrich From: SPSSX(r) Discussion <[hidden email]> on behalf of Chao yawo <[hidden email]>
Sent: Friday, February 3, 2017 8:40 PM To: [hidden email] Subject: TTest: Controlling for a 3rd Variable Hello, I am running a basic Ttest to estimate gender (varX) differences in income (varY). However, I want to segregate the analysis by 3 separate racial groups.
At the moment, Ttest only supports 1 variable on the groups command. A longer way is to limit the analysis to each group (using select cases), and run the Ttest repeatedly/separately.
Is there a different way to accomplish this in SPSS?

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Here's an example of the 3x2 ANOVA method Rich described. It uses EMMEANS with the COMPARE option to get M vs F contrasts at each level of race.
* Modify path on next line. GET FILE='C:\SPSSdata\survey_sample.sav'. UNIANOVA age BY sex race /METHOD=SSTYPE(3) /INTERCEPT=INCLUDE /EMMEANS=TABLES(race*sex) COMPARE(sex) ADJ(LSD) /CRITERIA=ALPHA(.05) /DESIGN=sex race sex*race. * See the last 3 tables in the output. * Take the square root of the Ftests * in the final table if you want to * report as ttests.

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