Model Prediction for pooled regression model in panel data
问题 I'm trying to produce a predictive model where i performed multiple pooled regressions in each year (based on previous years) and thus allow coefficients to vary across time. (This might not make sense in the sample data provided, but it is done in practice for my sample). Here is what I came up so far: I adjusted my code to a reproducible sample from the plm package: The data is structured in the following way (panel) with firm, year indexed. > head(Grunfeld) firm year inv value capital 1 1