On Jul 24, 2011 Gaiarrido wrote: > Why the order of the factors give different results? I suppose it's > because the order of the > factors, i've just changed "lcc" from the first position to the last in > the model, and the significance > change completely > ...snip < > Ijow can i know what's correct?
Both are correct. R's default anova uses sequential sums of squares and so tests model terms sequentially. Reordering the factors in your model therefore leads to different hypotheses being tested. You are looking for what are often called Type II tests. To get them use drop1() on your glm object or install the car package and use its Anova function. Regards, Mark. ----- Mark Difford (Ph.D.) Research Associate Botany Department Nelson Mandela Metropolitan University Port Elizabeth, South Africa -- View this message in context: http://r.789695.n4.nabble.com/GLM-different-results-with-the-same-factors-tp3690471p3690556.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
