```Date: Fri, 11 Jul 1997 16:54:17 EST Reply-To: peter homel Sender: "SPSSX(r) Discussion" From: peter homel Subject: answer to transform in repeated measures MANOVA Hi -- this is an update and answer to my own question about how to use a transform statement in a repeated measures MANOVA procedure in SPSS. I needed to have a way of getting polynomial contrasts on a repeated measure where the repeats were not of equal intervel (3, 4.5, 7.5, 10.5, 12) The answer is that you don't use MANOVA. Instead you use the GLM procedure in SPSS 7.5 (assuming you have access to it and use the contrast statement as follows: GLM deg3 to deg12 /wsfactors=degrees 5 polynomial(3,4.5,7.5,10.5,12) /wsdesign=year /print = parameter. The Advanced Statistics Manual for 7.5 on page 381 insists that you need to use integer values for the metrics (i.e., 30,45,75,105,120) but I get the same results using the actual values. By the way, speaking of the Advanced statistics manual for 7.5, it appears to contain a contradiction (dare I say error?) regarding the commands for a repeated measures MANOVA. On page 461 under the Syntax Rules, the manual states: Do not use the TRANSFORM subcommand with the WSFACTORS subcommand because WSFACTORS automatically causes an othonormal transformation of the dependent variables. [The WSFACTORS subcommand is of course essential for running the repeated measures procedure in the first place.] On page 464, the manual goes on to talk about CONTRAST for WSFACTORS: To perform non-orthogonal contrasts, you must use the TRANSFORM subcommand instead of CONTRAST. The TRANSFORM subcommand is discussed in MANOVA: Multivariate. Is it just me or do these two statements sort of contradict each other? These two statements have been in the Advanced manual since version 5, by the by. If the error is with me, then I aplogize in advance (advanced?). PETER HOMEL PHD HEALTH SCIENCE CENTER BROOKLYN STATE UNIVERSITY OF NEW YORK 450 CLARKSON AVENUE BOX 7 BROOKLYN, NY 11203-2098 EMAIL: HOMEL@SACC.HSCBKLYN.EDU HOMEL@SNYBKSAC.BITNET TEL: (718) 270-7424 FAX: (718) 270-7461 MOTTO: STATISTICS DON'T LIE!(PEOPLE DO!) ```

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