As bets take real time to place .
As there may be many actual profitable bets to place in a given race , the bettor may have to place bets before the final track odds have been set and thus may err ex post .
As bets take real time to place and as there may be many actual profitable bets to place in a given race , the bettor may have to place bets before the final track odds have been set and thus may err ex post .