I am doing logistic regression on some team stats for March Madness, where my response is 1 if "team A wins" and 0 if "team A loses". The problem with that is that the label "team A" is arbitrary. Indeed, my data are naturally labelled as winning team and losing team. However, the winning team can't be defined as "team A" because then my data is all 1s! How do I reformulate my problem to resolve this?