Re: calculating eta-squared for MANOVA with one IV

Posted by Swank, Paul R on Feb 21, 2010; 3:00am
URL: http://spssx-discussion.165.s1.nabble.com/calculating-eta-squared-for-MANOVA-with-one-IV-tp1092356p1092357.html

Multivariate R squared is 1 – Wilks’ lambda.

 

Dr. Paul R. Swank,

Professor and Director of Research

Children's Learning Institute

University of Texas Health Science Center-Houston

 

From: SPSSX(r) Discussion [mailto:[hidden email]] On Behalf Of Rayna Berlin
Sent: Saturday, February 20, 2010 4:39 PM
To: [hidden email]
Subject: calculating eta-squared for MANOVA with one IV

 

I am trying to calculate eta-squared for a MANOVA with one factor/IV and multiple DVs, using the syntax below. I'm using my ouput to manually calculate eta-squared--or trying to, at least! I'm trying to calculate eta-squared by

 SSb/SSt (the sum of SSb plus SS error), which is the same formula for calculating partial eta-squared, and indeed my manual calculations match the output for partial eta-squared. However, I don't want partial eta-squared. I think I read somewhere that with one IV these will be the same, but the total is greater than one, which doesn't make sense for eta-squared.

 

Any ideas on what I'm doing wrong? I don't have a MANOVA example for calculating eta-squared, and clearly whatever I'm doing isn't right. I need to provide eta-squared, not partial eta-squared. With only one IV/Factor, the only values I have for SSt are SSb and SSerror, whereas my ANOVA example has SS values for two IVs and their interaction, and the SS for error is included as well.

 

GLM V1 V2 V3 V4 V5 V6 V7 BY GROUP

/METHOD=SSTYPE(3)

/INTERCEPT=INCLUDE

/PRINT=ETASQ OPOWER

/CRITERIA=ALPHA(.05)

/DESIGN= REG_DIS_O.