I am trying to do a multinomial logistic regression to see if the type of food ( high,med, low prefernce) eaten by the primate that i am studying can be predicted by the proportion of different call types they give. there are 5 call types, some call types only given when they eat something they really like and some only fgiven when they dont like the food
when i try and run it, i get warning signs saying there are many cells with zero frequencies ( ie- dependent v levels by subpopulations)
why is this, and how to recify? for many of my cases,there are zeros for some call types ( ie- they do not produce call 5 when they like a food).
any advice greatly appreciated!