I've got some data on discrete flood events (response variable - duration) on several rivers.
I've modelled the response variable by site and time using a Generalized Linear Model:
mod = glm(duration ~ site + time)
I've then looked at the residual plots and cannot find any evidence for temporal correlation in the residuals. Does this mean that this model approach is valid (and that using a mixed/ random effects model is unnecessary) (or should one always use mixed/ random effects models for time-series data)?
Any links to reading references regarding this subject would be brilliant,