Say I want to create a model to predict outcomes of an emergency room, where the outputs are:
Why can't I run a linear regression model that assigns 1, 2, and 3 to Stroke, Seizure, and Overdose instead of creating a classification model? ISL (Friedman) makes the point that:
Unfortunately, this coding implies an ordering on the outcomes, putting drug overdose in between stroke and epileptic seizure, and insisting that the difference between stroke and drug overdose is the same as the difference between drug overdose and epileptic seizure.
However, why does the "difference", or "distance", matter? Can't I just take the output of the regression and round to the nearest integer and call that my guess?