I've not noticed any mathematical errors involved when a player loses at caravan, but when winning a hand, they'll receive double the amount that they're supposed to get. The issue appears to be that the player's money isn't being subtracted from his/her own pool of caps when the bet is placed, yet is being added to their total upon winning. For instance; if a player has 400 caps in their possession and bets 50 of that on a hand of caravan, then they should have 450 caps in total upon winning the hand - in actuality, they'll have 500.

This issue has been around pretty much since release, (in fact I originally posted about this in the general forum almost 1 year ago - http://www.gamesas.com/index.php?/topic/1131311-is-betting-on-caravan-games-bugged/), but should be a fairly straightforward fix. While this bug may not seem like too big of a deal to some, it's basically an unintentional form of cheating and trivializes the early game economy; it's not hard at all to make many thousands of caps off caravan before ever reaching the strip for the first time (and since the player doesn't lose double the correct amount when they don't win, the risk factor is relatively low).