[R] Correct nested design for GLM

Hi, I am currently running the following negative binomial GLM: glm89.nb <- glm.nb(AvGUD ~ Year*Trt*Micro + (0 + Micro/Trt/Year)) where Year has 3 levels, Trt has 2 levels, and Micro has 3 levels. >From what I have read the above model has a 3 way interaction (Year*Trt*Micro), and Micro is nest

[R] Zero inflated negative binomial

Hi all, I am running the following model: > glm89.nb <- glm.nb(AvGUD ~ Year*Trt*Micro) where Year has 3 levels, Trt has 2 levels and Micro has 3 levels. However when I run it has a zero inflated negative binomial (as I have lots of zeros) I get the below error message: > Zinb <- zeroinfl(AvGU

[R] LMM and unequal variances

Hi all, I am running a LMM and have two fixed factors: Trt (with 2 levels) and Microhabitat (with 3 levels), and a randon factor: Group nested within Trt. I have unequal variances between the two Trt levels. Does this matter in a LMM? Thanks for your time Rebecca [[alternative HTML vers