Keno is a Popular Game
The popular lottery-style game of keno is thought to have originated somewhere in China, but is now enjoyed online and in casinos worldwide. Simple to learn but difficult to master, keno attracts players of all levels, from recreational gamer’s right through to professional gamblers with a knack for playing the odds. There is one element that can work to deter the amateur gamer however, and that is the question of how best to calculate keno odds.
Understanding the Game
Keno players select between one and twenty ‘spots’ (numbers one through eighty), and when a series of numbers is then revealed, those that match your spots are called hits. The higher your proportion of hits per spots, the higher the odds you get and the higher your score. The real skill lies in anticipating how many hits you’re likely to get.
Pick too many spots and you’ll lower your odds, too few and you risk missing out on a high score. There are a number of formulae and algorithms one can use to calculate the exact odds in a game of keno, most of which look something like this
C(N,K) * C(80-N,20-K) p(N,K) = C(80,20)
(Where n equals the number of spots and k the number of hits)
The number that actually do are called “caught”. So you start with a matrix of picks and catches and the odds of each.
Now create a matrix of payouts for all the combinations
Finally multiply the top table by the bottom table. This is what is expected payout for $1 bet.
Once you figure out the odds of actually winning keno and the payoffs the casino gives, you will realize that the house does not pay what the actual odds are. The math is always on the house’s side. Many players say to stay away from keno because of the high house advantage, which can be up to 20 percent. Suppose to catch one number, the real odds are 25 percent or 4 to 1. For the odds to be perfect, the house should pay $4 for every $1 bet. But in reality, the house pays $3 for $1 bet. That 25 percent difference is the “edge” the house possesses.
There are also some online calculators that can help shortcut figuring out the odds.
Higher the Odds, Higher the Payout
Don’t worry if you’re finding all this math intimidating though, because while calculating keno odds may be complicated, understanding the odds in the context of the game is actually rather simple. In the traditional approach to the game, players select a number of spots depending on which numbers are hot or cold, or how lucky they feel.
The more hits they get with the least number of spots, the higher the odds and the higher the payout. For example, if a player thought that they were likely to pick six correct numbers, they could either choose to play six spots, maximizing their potential jackpot to $500, or as many as fifteen spots, increasing their chances of achieving more hits but lowering the odds so that the same six hits would award a mere $2.
So, while the question of how to calculate keno odds is a difficult one, applying those rules to the game itself is actually quite simple.