Coefficients of Determination for Mixed-Effects Models

The coefficient of determination is well defined for linear models and its extension long wanted mixed-effects in agricultural, biological, ecological research. We revisit to define measures proportions variation explained by the whole model, fixed effects only, random only. propose calculate unexplained variations conditional on individual and/or so as keep heterogeneity brought available predictors. While these were naturally mixed models, they can be a generalized model using distance measured along variance function, accounting heteroscedasticity. demonstrate promising performance utility our proposed methods via simulation studies applications real data sets agricultural studies.