Hi, I'm doing a MANOVA for the first time in SAS and I have a few questions. I would appreciate any help that people can give. My design is kind of complicated, so let me briefly describe it. I am measuring the shape of a fin of a fish. To so this, I have 3 different metrics: BLResid, SAResid, and AngleResid. I want to know whether habitat, drainage, or sex (or any of their interactions) influence shape. I also need to consider the population they are from in order to avoid pseudo-replication (different fish from the same population may not be considered independent). Population is also nested within habitat*drainage. However, I need to specific the error term because I would like to test the main effects (habitat, drainage, or sex) or their interactions over either their interaction with population or sex*population. So, for instance, I need to test habitat over population(habitat*drainage). The same is true for drainage and habitat*drainage. For population(habitat*drainage), sex, and all interactions with sex (sex*habitat, sex*drainage, sex*habitat*drainage) I need to test over sex*population(habitat*drainage). Really, the ONLY term being tested over the "normal" error is sex*population(habitat*drainage). Here is the code I'm using: proc glm data = dfin0; class habitat sex drainage population; model BLResid SAResid AngleResid = habitat sex drainage habitat*drainage sex*drainage sex*habitat sex*habitat*drainage population(habitat*drainage) sex*population(habitat*drainage); manova h = _ALL_ e = sex*population(habitat*drainage); run; What I've been doing is just changing the " e = " part to change it accordingly. So, for habitat, drainage, and habitat*drainage " e = " is changed to " e = population(habitat*drainage) " (without the quotes, of course). Here is the output I get (I apologize if the formatting is off): MANOVA Test Criteria and Exact F Statistics for the Hypothesis of No Overall Habitat Effect H = Type III SSCP Matrix for Habitat E = Type III SSCP Matrix for Popul(Habita*Draina) S=1 M=0.5 N=-0.5 Statistic Value F Value Num DF Den DF Pr > F Wilks' Lambda 0.52984406 0.30 3 1 0.8368 Pillai's Trace 0.47015594 0.30 3 1 0.8368 Hotelling-Lawley Trace 0.88734776 0.30 3 1 0.8368 Roy's Greatest Root 0.88734776 0.30 3 1 0.8368 That is the output for Habitat. I have similar output for all terms in the model, but I didn't think it was necessary to copy them all into this forum. Here are my questions: 1. Is my code correct for what I am trying to do? 2. Where are those DFs coming from? I only have 2 habitats (lakes and streams), so why is the "Num DF" 3? Shouldn't it be 1 (2 minus 1)? Similarly, if I'm testing over population(habitat*drainage), why is "Den DF" only 1? I have 9 populations. Shouldn't it be 8 (9 minus 1)? These are my questions and I'm hoping someone can help, because until someone does, I'm not confident I'm doing the MANOVA properly. ANY help would be greatly appreciated! Thank you!!
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