I'm new in the forum and also I'm a beginner on a mixed effect model using lme4 package in R. After reading lot of questions and answer in different forums and also several tutorials and book chapters, I still have some doubts about my formulation of my model. I've done an experiment with two fixed effects and two levels each (Pollution: Yes/No, and Temperature: 17°/22°) and one random effect with 5 levels (Population: 1, 2, 3, 4, 5) that is nested on Pollution effect. For each combination I have 6 replicates. I'm interested on the effect of Pollution and Temperature on the fertilisation success. So I was considering the following model:
y = Pollution(Population) + Temperature + Pollution(Population)*Temperature + err
Hoping that my model includes Population as a random effect nested in Pollution and accounting for interaction with temperature I've been able to piece together the following:
model1<-lmer(rto_Embryos~ Pollution + (1|Pollution:Population) + Pollution*Temp + (1|Replicate), data=mydata, REML=F)
Is this accurately expressed? Any suggestions for how to improve my code if it does not correctly depicted?
Thank you very much in advance...