“Video poker is the worst of the worst. The reason it works so well is it compels you to keep playing through random reinforcement,” he said. “The next hand might be the big one. You might get a flush or a full house, and that keeps you hanging in there. It gives you just enough positive feedback to keep you hooked into it.”

The elimination of most machines that don’t have a broad, built-in house edge has narrowed the field of those who are ready to drop millions, said Jean Scott, who has written several books about video poker and has played at a professional level for decades. “The advantage plays have gone away in recent years. It is getting hard to win,” Scott said. “The casino bean counters are getting tougher.”