Negative Incremental Values: Modified log-link

Negative incremental values occur when a response variable increases as the predictor variable decreases. The Modified Log-Link is a function used to model such a situation, as it takes a logarithmic inverse of the response variable in order to “flip” its sign. This Modified Log-Link is useful when the independent variable has a negative correlation with the response variable, and when the expected values are either all negative or a mix of positive and negative values.