You can use any model you want, as long as it’s linear and has a positive slope

It is inherently challenging to use a model to make predictions beyond the range of data to which the model was fit — making predictions about the future, for example, based on the past and present. Or, as the Danish proverb more elegantly says, “It’s difficult to make predictions, especially about the future.” Still, there’s … Continue reading You can use any model you want, as long as it’s linear and has a positive slope