topic Re: glimmix: dispersion estimates for small samples in Statistical Procedures https://communities.sas.com/t5/Statistical-Procedures/glimmix-dispersion-estimates-for-small-samples/m-p/85251#M4160 <HTML><HEAD></HEAD><BODY><P>I would go with the empirical= option for this, unless you have a lot of missing data.&nbsp; If you are on SAS/STAT 12.1 or higher, consider ddfm=KR2, the improved Kenward-Rogers adjustment.</P><P></P><P>Steve Denham</P></BODY></HTML> Tue, 24 Sep 2013 17:57:06 GMT SteveDenham 2013-09-24T17:57:06Z glimmix: dispersion estimates for small samples https://communities.sas.com/t5/Statistical-Procedures/glimmix-dispersion-estimates-for-small-samples/m-p/85250#M4159 <HTML><HEAD></HEAD><BODY><P><SPAN style="color: #000000; font-family: Arial, sans-serif; font-size: 16px; background-color: #ffffff;">I am interested in the topic of dispersion estimates for count data coming from RNAseq data. The glimmix procedure provides the option empirical=mbn to correct for small sample size,and it appears to have good statistical properties in terms of type I error rates, however there is also the possibility to adjust the denumerator degrees of freedom for the F-tests with the KenwardRoger method. Does anybody have an idea what the best choice is? In our experiments, we typically only have 3 biological replicates for each treatment.</SPAN></P></BODY></HTML> Tue, 17 Sep 2013 19:08:41 GMT https://communities.sas.com/t5/Statistical-Procedures/glimmix-dispersion-estimates-for-small-samples/m-p/85250#M4159 vstorme 2013-09-17T19:08:41Z Re: glimmix: dispersion estimates for small samples https://communities.sas.com/t5/Statistical-Procedures/glimmix-dispersion-estimates-for-small-samples/m-p/85251#M4160 <HTML><HEAD></HEAD><BODY><P>I would go with the empirical= option for this, unless you have a lot of missing data.&nbsp; If you are on SAS/STAT 12.1 or higher, consider ddfm=KR2, the improved Kenward-Rogers adjustment.</P><P></P><P>Steve Denham</P></BODY></HTML> Tue, 24 Sep 2013 17:57:06 GMT https://communities.sas.com/t5/Statistical-Procedures/glimmix-dispersion-estimates-for-small-samples/m-p/85251#M4160 SteveDenham 2013-09-24T17:57:06Z