Maximizing Value in Free Plays at Sportsbooks
 

I liked this article. I'd like to point out the similarity of the free plays with sticky bonuses offered by some online casinos.

A sticky bonus is added to your balance when you deposit, and removed when you withdraw. To take advantage, you must risk going bankrupt, which means the bonus is not removed. The value of the bonus is at most p*B, where p is the probability of busting out, and B is the nominal size of the bonus. A similar expression bounds the value of a free play.