All, This may be a bit off topic so feel free to flame me ... my defence is that I am using R. I have data with case counts per family. I arrange the data in a simple table of frequency classes (e.g. how many families with 0 cases, how many with 1 case, &c.) and then GoF to Poisson and negative binomial. I treat each family as a natural sampling unit but families are of different size. I can do the above analysis for each family size but would like to pool the results. Which way forward ... I am guessing that I could use some extension of Mantel-Haenszel methods or maybe a GLM. Any pointers gratefully received. Mark -- Mark Myatt -.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.-.- r-help mailing list -- Read http://www.ci.tuwien.ac.at/~hornik/R/R-FAQ.html Send "info", "help", or "[un]subscribe" (in the "body", not the subject !) To: r-help-request at stat.math.ethz.ch _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._