Abstract: A probability of winning at least one of a plurality of prizes for a contest is dynamically adjusted, given a fixed prize inventory and an a priori unknown number of participants. A variable probability is determined by approximately dividing a current number of participants in the contest by a current number of prizes awarded. The variable probability is dynamically adjusted based on a variable probability multiplier, that is obtained by dividing a current number of winners in a predefined time interval by a remaining number of prizes in the predefined time interval. A prize can be awarded based on the adjusted variable probability.

Abstract: Methods and apparatus ale provided for dynamically adjusting a probability of winning at least one of a plurality of prizes for a contest, given a fixed prize inventory and an a priori unknown number of participants. A variable probability is determined by approximately dividing a current number of participants in the contest by a current number of prizes awarded. The variable probability is then dynamically adjusted based on a variable probability multiplier. The variable probability multiplier is obtained by dividing a current number of winners in a predefined time interval by a remaining number of prizes in the predefined time interval. The current number of winners in the predefined time interval is substantially equal to the current number of prizes awarded divided by an elapsed number of the predefined time intervals in the contest.