Add interpretations of parameters

When possible, we should add explanation and interpretation of parameters in the models. In particular for GLMs we can add what the relation between the beta and the outcome will be (depending on the link)

Start by locating the model entries and identifying which GLMs and parameters the issue refers to; the issue names no files or tests. Determine how the link function relates beta to the outcome, then consider the work done when relevant model parameters have explanations and interpretations.

Written by the indexing model from the issue text.