specifying multiple separate random effects in nlme
问题 I am analysing some whale tourism data and am trying to construct linear mixed effect models in the nlme package to see if any of my explanatory variables affect encounter time between whales and tourists. (I am also open to running this model in lme4 .) My variables are: mins : encounter time (response variable) Id : individual whale ID (random effect) Vessel : vessel Id (random effect) Sex : sex of the animal Length : length of the animal Year Month (nested within Year ). So my random