Hi all! My question is why, and what I can do about that I sometimes, but not always, get warning-messages like
nlminb returned message singular convergence (7) in: LMEopt(x = mer, value = cv) or IRLS iterations for PQL did not converge when trying to fit a model looking like this: lmer<-(cbind(Diseased,Healthy)~Fungus+(1|Family)+(1|Fungus:Family), family="binomial") to four similar data sets? All four data sets consists of four columns; Fungus (1 or 2), Family (1-30), Diseased and Healthy. An example: Fungus Family Diseased Healthy 1 1 3 7 2 1 1 5 1 2 2 16 2 2 2 14 ...and so on up to totally 30 families. One of the data sets works perfectly fine and gives no warnings, but for the others i get different amount of warning messages. Between the data sets it is only the number of diseased anf healthy for each family and fungus that differ. Does anyone have any idea why this happens and how I can get around it (I'm mainly interested in the interaction term...)? Grateful for any help /Åsa __________________________________________________________________ Åsa Granberg, Doktorand / Phd-student Evolutionär ekologi Ekologi, miljö och geovetenskap Umeå Universitet 901 87 Umeå Evolutionary ecology Department of Ecology and Environmental Science Umeå University 901 87 Umeå, Sweden Phone: +46 (0)90 786 7461 Fax: +46 (0)90 786 6705 e-mail:[EMAIL PROTECTED] ______________________________________________ R-help@stat.math.ethz.ch 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.
