I'm not sure if this is the right place for this question, apologies if I'm out of order.
I am trying to predict horse racing data where I have a set of features for each horse in a race, and also a results data set where I know which horse wins.
I am a little confused about how best to structure the data in a manner that the probabilities of predictions for a particular race end up summing to 1.
In all other machine learning tasks I have done prior to this, each prediction is independent of others, but in this case a bunch of rows all belong to the same 'group'.
Any ideas will be highly appreciated. Thanks very much.