Open Problem : How To Make Residual Plots For Multilevel Models ( Or For Regularized Bayesian And Machinelearning Predictions More Generally ) Statistical Modeling , Causal Inference , And Social Science On day 116 of the year 2023 which happened to be a Wednesday in the month of April Open problem : How to make residual plots for multilevel models ( or for regularized #Bayesian and #MachineLearning predictions more generally ) ? #Statistical Modeling , Causal Inference , and Social Science