Calculates the (Pearson) residuals of a fitted model for model evaluation purposes.
Value
a list that includes the (Pearson) residuals, conditional expectations, conditional variances, and information on the model specifications.
Details
The Pearson residuals are computed as the scaled deviation of the observed count from its conditional expectation given the relevant past history, including covariates, if applicable. If a fitted model is correctly specified, the Pearson residuals should exhibit mean zero, variance one, and no significant serial correlation.