Dear SAS users, We have some doubts with a longitudinal analysis using GLIMMIX and hope someone could advise us. We have daily movement data (Euclidean distances) of 45 individuals of a large bird of prey monitored during seven years which, in total, summed 18574 observations. Birds are evenly distributed in three different regions and no bird moved between regions. We are interested to know if daily movements differed among regions after controlling for bird age. The model we constructed was: PROC glimmix DATA=COMP.PREDISP method=laplace; CLASS birdidentity region year; model distdiar= region age region*age /dist=XXX s; random int / sub=birdidentity; random int /sub=year; LSMEANS REGION/DIFF CL; run; Model results (Type III tests of fixed effects) show 15298 denominator degrees of freedom. The model is considering both within and between individual variation, so we are wondering if this procedure “artificially” inflates (in our particular case) degrees of freedom to the point that results could be wrong. Any suggestion? Thank you very much in advance David
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