Statistical analysis of repeated measures data using SAS procedures.

  title={Statistical analysis of repeated measures data using SAS procedures.},
  author={Ramon C. Littell and Pamela R. Henry and Clarence B. Ammerman},
  journal={Journal of animal science},
  volume={76 4},
Mixed linear models were developed by animal breeders to evaluate genetic potential of bulls. Application of mixed models has recently spread to all areas of research, spurred by availability of advanced computer software. Previously, mixed model analyses were implemented by adapting fixed-effect methods to models with random effects. This imposed limitations on applicability because the covariance structure was not modeled. This is the case with PROC GLM in the SAS System. Recent versions of… 

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