Hi, I am trying to figure out what is causing disparity between the urchin population at 2 different reef sites and decided to use a GLM. However, I am unsure as to how I can add location as a fixed factor, rather than an explanatory variable. Here is my code so far:
model6<-glm(Diadema~Location*ET*Scar*Poma*Lab*HAS*Rock, data = Full10, family = quasipoisson(link = log)) summary(model6)
What should I change to fix this issue?