Hi, I am an M.S. student at the University of Washington School of Aquatic and Fishery Sciences.My thesis involves the comparison of many models that you could use to analyze monitoring data. A big part of this comparison is looking at models with and without autocorrelation (my data is a univariate time series). I was hoping to compare a GLS, GLM, and GLM with autocorrelation for a non-normal data set using their RMSE values. I was originally intending to use a GLM-GEE, because I have seen them used in the literature within my field, but I noticed the glmmPQL function allows for different corARMA correlation structure and the gee only allow for an ar-1 correlation structure. So now, I believe that I would rather use the glmmPQL for the purpose of comparing a model that allows for autocorrelation but is normally distributed (GLS), one that is non-normal with no autocorrelation (GLM), and one that is non-normal with autocorrelation. I am wondering if there is a big difference between the glmmPQL model and a glm-gee? I know the gee is a marginal model, and a glmm models random effects, but in the case of a univariate time series (which is essentially a single group) I am not sure how this would make a big difference. If anyone has any time to provide suggestions on better understanding the difference between these two models, or if it is appropriate to use a glmm rather than a gee in this case, I would greatly appreciate it. Thank-you very much, Hannah Linder
GLMMpql and GEE question
1 message · Hannah L. Linder