Dear BioCers, Has anyone implemented Friedmans or Quades Test (a non-par. 2-way anova) for use on the AffyBatch class? I have a strong batch effect between half my biol. replicates. Rather than (continue) attempting to pull the two batches together with a fancy normalization, i thought i might try this test since my 3 tissues come from the same animal, ie. are paired. Or perhaps, some one *does* have experience normalizing a large batch effect? Suggestions and advice greatly appreciated, Karl -- Karl Brand <k.brand at="" erasmusmc.nl=""> Department of Genetics Erasmus MC Dr Molewaterplein 50 3015 GE Rotterdam lab +31 (0)10 408 7409 fax +31 (0)10 408 9468