Hi, I do have replicates, but not many. The offsets are my the number of replicates actually, i misled myself by thinking i could add the counts of the replicates all up and then go further with the offset function. I decided to split up my experiments in order to interpret them, they were actually from the beginning split up experiments. Because i thought i could see if the bees reacted in a same manner to the different experiments i thought i could analyse it with an interaction factor to reveal whether this was true. But i want now want to analyse them apart so i can draw conclusions from the both experiments apart. I did the following with the counts from p1, including the replicates so i have only the type of field-margin as a variable, as i was only interested in this from the beginning: mengsel count C 39 C 38 A 79 A 96 A 278 D 15 D 15 B 322 B 449 B 262
a.data.p1<-read.table("a.data.p1.txt",header=TRUE,sep="") a.data.p1 fit.sat.a.p1<-glm(count~mengsel,data=a.data.p1,family=poisson) anova(fit.sat.a.p1,test="Chisq") fit.main.a.p1<-glm(count~1,data=a.data.p1,family=poisson) anova(fit.sat.a.p1,fit.main.a.p1,test="Chisq") extractAIC(fit.sat.a.p1) extractAIC(fit.main.a.p1) summary(fit.sat.a.p1) This tells me that the saturated model is better explaning then the other so: Call: glm(formula = count ~ mengsel, family = poisson, data = a.data.p1) Deviance Residuals: Min 1Q Median 3Q Max -6.4531 -3.7799 -0.0404 0.0603 9.2385 Coefficients: Estimate Std. Error z value Pr(>|z|) (Intercept) 5.01728 0.04698 106.79 <2e-16 *** mengselB 0.82433 0.05635 14.63 <2e-16 *** mengselC -1.36662 0.12327 -11.09 <2e-16 *** mengselD -2.30923 0.18852 -12.25 <2e-16 *** --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 (Dispersion parameter for poisson family taken to be 1) Null deviance: 1385.58 on 9 degrees of freedom Residual deviance: 202.01 on 6 degrees of freedom AIC: 273.15 Number of Fisher Scoring iterations: 5 How can i produce a graph for this? I am worried that i still do not have enough replicates to actually draw descent conclusions or conclusions at all...in my second experiment i do not have replicates for 2 out of four types of field margins, for the other two i only have 2 replicates. this being the counts from the second experiment: C 3 p2 C 1 p2 A 90 p2 A 29 p2 D 0 p2 B 157 p2 thanks, babs -- View this message in context: http://r.789695.n4.nabble.com/producing-a-graph-with-glm-poisson-distributed-respons-count-data-and-categorical-independant-variabs-tp4638110p4638192.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org 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.