The link test was ran for a possion model.
This picture was taken out of the Negative binomial regression textbook by Joseph Hilbe.
The link test was ran for a possion model.
This picture was taken out of the Negative binomial regression textbook by Joseph Hilbe.
If your model is properly specified, then you should not be able to find any additional predictors that are statistically significant. This command uses the predicted value from the poisson (_hat) and the predicted value squared (_hatsq) as the predictors and re-estimates the model. It's a kind of variable augmentation test.
The variable _hat should be a statistically significant predictor. This should be the case unless the model is utter junk. The variable _hatsq should be insignificant. If it is, this usually means that you omitted relevant variables and/or the link function is not correctly specified.
You can tell that you flunked by the low p-value or the confidence intervals on _hatsq not containing zero.