glmer混合模型在lme4更新之间不一致

This is a long post. I’m having trouble attaining consistent model results between lme4 versions. My old computer was running R 3.0.0 “Masked Marvel”, with the 0.999999-2 version of lme4, and my new work computer is running R 3.0.2 “Frisbee Sailing” with lme4 version 1.1-2. They are not giving me the same model outputs. Omitting the new lme4, I installed every package update on my old laptop one-by-one and ran the models. Then, updated R itself and ran the models. Finally, I made further updates to packages for R 3.0.2, and ran the models once more. They remained consistent with the original analysis. I wasn’t able to run the models with the most recent MASS package with R 3.0.0, and with the most recent nlme package in R 3.0.2. The error message I received in those cases was the same, and is below: “Error in validObject(.Object) : invalid class “mer” object: Slot L must be a monotonic LL' factorization of size dims['q']”This is a long post. I’m having trouble attaini