State lab keeps the chance in casino games of chance

| Friday, Dec. 14, 2012, 8:54 p.m.

Michael Cruz can walk out of his office and hit a slot machine jackpot any time he wants.

The only catch is that he can't collect the cash.

As director of Pennsylvania's Gaming Laboratory Operations, which tests slots and all other equipment used in gambling areas of the state's casinos, Cruz can have his staff program the lab's slot machines to hit a specific payout. That allows them to verify a machine pays out the number of credits it's supposed to, without the tester having to wait for a lucky spin as a casino patron would.

"We'll force the jackpot," says Cruz, standing in the Harrisburg lab, which holds more than 100 slot machines plus various gaming tables and other casino gear.

In a casino, slot reels spin according to the whims of a random-number generator, software whose sole function is to spit out groups of numbers.

Each number corresponds to a specific symbol on a reel of the display. The number combination generated at the instant a player hits the spin button determines what symbols will be displayed.

In the lab, "we cut the RNG out," Cruz says. Using software and codes provided by the manufacturer, a tester with access to the machine's "brain" enters the numbers corresponding to a jackpot.

"We restart the game and let it evaluate that combination," he says. Indicating a Game of Life machine, he explains that if five Game of Life symbols pay a jackpot, the tester verifies that five symbols show up - one on each reel ­- and that the game pays the promised jackpot value. Cruz says that in almost 10 years as a gaming regulator in New Jersey and Pennsylvania, he's encountered only one case of a machine failing a lab-payout test.

Pennsylvania, which has more than 26,000 slots and is among the top three states in gambling revenue, is one of the few jurisdictions with its own lab. Other than Nevada, New Jersey and Michigan, most states hire a private lab to test their machines. Slot manufacturers pay for Pennsylvania's testing.

"We are here to ensure that when a patron sits down at a game, they have a fair shake, that it's a fair game between them and the computer," Cruz says. "If they lose or they win, it was by luck and not by any other reasons."

The gaming lab has three main responsibilities:

• Verifying the math: Pennsylvania requires slots to have a theoretical payout rate of 85 percent to 99.999 percent. Statisticians review the probability of each possible combination and the proposed payment to make sure the long-term payout rate falls within that range. Manufacturers provide that information in top-secret PAR sheets, short for Probability Accounting Reports. In Pennsylvania and elsewhere, those are considered proprietary information, but a handful have become public. For samples, go to From July 2011 through June 2012, the lab rejected 3,350 of the 14,215 pay tables it examined.

• Engineering: This verifies not only that the machine pays as promised, but also that it communicates with the state's central computer system, which constantly monitors the coin-in and coin-out of each machine in the state.

• On-site review: Staffers examine complaints of machine malfunctions and monitor installations or changes on the floor.

Casinos can choose from as many as 20 payback percentages on a single slot machine, Cruz says. They might switch from one rate to another, as long as it meets the state minimum and they notify the lab of the planned change. Such notifications are not considered public record.

The payback percentage can be tweaked in a couple of ways. One, obviously enough, is raising or lowering the payouts, generally for a few common combinations. Another is to keep payouts the same but change the number of symbols on the reel or the probability of hitting them.

Players have no way of knowing the payout rate at a traditional slot machine, as opposed to a video poker machine.

State law specifies that no slot-payoff combination can have odds of more than 50 million to one, Cruz says. Odds that high would likely be for the big payout on a progressive jackpot.

No matter how long the odds, each spin has an equal chance of hitting a jackpot.

"What we do here is to preserve that aspect," Cruz says. "Random chance (is) the reason why your outcome came the way it did. There's no other ulterior motive behind your winning streak, your losing streak or whatever."

Mark Gruetze is administrative editor for Trib Total Media. He can be reached at 412-320-7838 or

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