A link function maps the interval (0, 1) onto the whole real line. This guarantees that the predicted probability of an event using the model produces a number between 0 and 1. Minitab provides three link functions:
- Normit (probit)
- Gompit (complementary log-log)
Use the link function to find a model that best fits your data. Use the goodness-of-fit statistics to compare fits using different link functions. Certain link functions can be used for historical reasons or because they have a special meaning in a discipline.
One advantage of the logit link function is that it provides an estimate of the odds ratio for each predictor in the model.