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How can video poker be random and machines have fixed paybacks?

18 September 2006

John,

If, in Nevada, for example, the dealing of cards on a video poker machine has to be as random as those being hand dealt, how can any video poker machine have a fixed payback or house edge?

John

Dear John,

For the same reason that a slot machine can choose symbols at random and still have a calculable long-term payback.

What's random is the card that will be drawn next. What isn't random is the probability of making any particular hand and what that hand is worth.

Consider the dealt hand in video poker. There are 2,598,960 hands you can be dealt. We don't know what hand will be dealt when you press the Deal button, but we do know that only four of them are royal flushes. Likewise, there are only 624 ways to be dealt four of a kind.

The discard complicates matters and makes it much harder to figure out the number of ways you'll make different hands. But the fact remains that the strategy you follow determines the probabilities with which you'll achieve the various paying hands. When you combine those probabilities with the values of the hands, you get the machine's long-term payback.

Best of luck in and out of the casinos,
John

Dear John,

A couple weeks ago, a bus went from here to Caesars in Southern Indiana and this is the story.

A lady and her husband were playing the \$2 machines and kept hitting. When the bus was due to leave, she came out and told the driver to go on back and that they had a hot machine and were going to stay.

They ended up hitting over and over and cashing in the tickets as they played and ended up with almost \$80,000.

My question is, why didn't someone figure out something was wrong with the machine and come fix it?

I have seen them do this at the Blue Chip after a gentleman hit four times in a row and an attendant came and opened the machine and it never paid after that.

They said they didn't have to pay taxes on this money and I don't understand what happened. They rented a car and came back the next day.

Am I wrong or do the upper rooms pay attention to these machines that are doing this?

Too bad it wasn't me. A change machine was kicking out \$100 dollar bills and they caught this, so can you tell me what happened here?

Lou

Dear Lou,

My question is, why do you think there was something wrong with the machine?

Machines have hot and cold streaks. It looks this couple was lucky enough to have found a machine on an extended hot streak.

There's nothing that the casino can do to make a machine hit more or less frequently. It's just a coincidence that the machine at the Blue Chip didn't pay again after the attendant opened it.

Slot Management does pay attention to the performance of their machines. But it's not unusual to have machines that are particularly generous or stingy on any given day. The overall performance of the machines is still in line with their long-term paybacks.

The couple does have to pay taxes on the money they won. All of their wins must have been less than \$1,200 or they would have been given tax forms. But just because a win wasn't reported to the IRS, that doesn't mean that you're not responsible for paying the taxes on it.

Thanks for the kind words about my column,
John

I am new to slot machine playing, so forgive me if my question appears so juvenile… Are you more likely to hit something playing higher denomination machines versus lower denomination machines?

In other words, is the payback percentage on a machine increased because of the dollar denomination of the machine?

Thanks for getting me started,
Cheryl

Dear Cheryl,

You're actually asking two completely separate questions. Your first question has to do with hit frequency and the second with long-term payback. The two are not related.

Let's start with your second question. Long-term payback does tend to increase with denomination. Because more money gets played through the higher denomination machines, the casino can afford to take a smaller percentage of the money played through those machines and the machines can still make enough money to pay for their places on the slot floor. Higher denomination machines tend to have higher long-term paybacks.

Having a higher long-term payback does not mean you are more likely to hit something on a machine. Machines can have high long-term paybacks and low hit frequencies.

That said, many slot directors do order high hit frequencies on their high denomination machines. Passersby like to see players hitting something, even small payouts, on high denomination machines.

We can prove that higher denomination machines have higher paybacks by looking at the paybacks reported in Casino Player and Strictly Slots magazines, but that doesn't tell us anything about the hit frequencies on those machines.

Best of luck in and out of the casinos,
John

Hi, John,

Greetings from New Zealand.

There is a slot game here called Queen of Sheba where 15 free spins are triggered if three certain symbols come up.

After the spins are complete another screen is displayed offering three choices:

• Accept the credits just won
• Accept a mystery number of credits
• Re-play the 15 free spins (before starting it removes the credits won on the first lot of free spins)

The screen also advises which two options can offer the optimal choice. In my way of thinking, the only way this can happen is if the machine pre-plays the 15 free spins internally prior to offering the three choices. This would make this game function differently from the others which have a free spins feature. Am I correct?

With the normal 15 free spin games does the RNG generate 15 lots of numbers as soon as you hit Start Feature or does it generate the next number after completing playing the previous game?

I'm sure you've answered this question before, but does a five-reel machine generate one random number or five to determine the stop position on the reels?

Many thanks.

Regards,
Ken

Dear Ken,

To rank the choices, the machine has to know the expected value of each choice. The expected value (EV) of the credits won is easy. It's the credits won.

The EV of 15 free spins is just 15 times the EV of one spin. The EV of a spin is the machine's long-term payback. We don't know the machine's long-term payback, but the programming running the machine does. So the program can figure out the EV of the free spins.

The EV of the mystery credits is, well, a mystery. We don't know how the machine chooses the value, but the machine does. The machine therefore knows the EV of choosing the mystery credits.

Presumably, the machine recommends the two choices with the highest EVs, but I don't really know what is meant by "optimal". In any case, the machine does not have to pre-play the 15 spins to know their EV, but it would if it needed to know their actual value. Same thing with the mystery credits. The EV is known without choosing a value, but not the actual value chosen this time around. I don't think this machine operates any differently from other machines with a free spin feature.

As for polling the RNG for the free spins, the machine more than likely does not get the results for all 15 spins at once. Instead, it determines the result of a spin shortly before it is displayed.

As for whether a five-reel machine uses one number or five, it doesn't matter. Either method yields sufficiently random results. That said, most machines use one number per reel.

Best of luck in and out of the casinos,
John

Hi, John,

It's funny, I come home from work (I am the Kitchen Supervisor at Point Edward Casino) and find your newsletter waiting for me, as we were talking about slot machines in the break room today.

My question to the Slot Manager was, would they ever make Braille slot machines?

We got talking more about it and it was decided I should put that question to the Ontario Lottery and Gaming (OLG), which I work for.

Before I make a fool of myself with my company, I'll ask you. Have you ever heard of such a thing? Has anyone ever brought it up?

Give me your thoughts on this. Have I come up with something here?

Let me know.

Chef Di

Dear Chef Di,

Bally, a few years ago, had a line of Ray Charles slot machines that had features designed for blind players. I don't see the machines listed on the Bally site, so I don't think they make them anymore.

John

Send your slot and video poker questions to John Robison, Slot Expert, at slotexpert@comcast.net. Because of the volume of mail I receive, I regret that I can't send a reply to every question. Also be advised that it may take several months for your question to appear in my column.

John Robison

John Robison is an expert on slot machines and how to play them. John is a slot and video poker columnist and has written for many of gaming’s leading publications. He holds a master's degree in computer science from the prestigious Stevens Institute of Technology.

You may hear John give his slot and video poker tips live on The Good Times Show, hosted by Rudi Schiffer and Mike Schiffer, which is broadcast from Memphis on KXIQ 1180AM Friday afternoon from from 2PM to 5PM Central Time. John is on the show from 4:30 to 5. You can listen to archives of the show on the web anytime.

Books by John Robison:

The Slot Expert's Guide to Playing Slots
John Robison
John Robison is an expert on slot machines and how to play them. John is a slot and video poker columnist and has written for many of gaming’s leading publications. He holds a master's degree in computer science from the prestigious Stevens Institute of Technology.

You may hear John give his slot and video poker tips live on The Good Times Show, hosted by Rudi Schiffer and Mike Schiffer, which is broadcast from Memphis on KXIQ 1180AM Friday afternoon from from 2PM to 5PM Central Time. John is on the show from 4:30 to 5. You can listen to archives of the show on the web anytime.

Books by John Robison:

The Slot Expert's Guide to Playing Slots