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8 March 2002

Hi there,

I recently obtained a copy of a free e-book off the Internet from a web site www.slot-secrets.com. The book was written by Andre Roodt (apparently a slot machine technician) and described in detail the workings of a slot machine, including the way payouts are calculated and the part that stops and the Random Number Generator play in this process. As someone who has had some exposure to Mathematics, I was able to follow this principle of "combinations" which result from multiplying the number of stops on each reel by each other to get the total number of possible result combinations.

What I would like to know, however, is the following :

A slot machine seems to have a better "rate of payout" when the player increases the amount he spends on a spin. In other words, if I spend \$3 per spin instead of \$1 per spin, I usually get more payout hits. How does the software program in the slot machine adjust for the fact that I'm spending more money per spin? Because, from what happens within the "electronic workings" of a slot machine, the Random Number Generator generates 3 numbers, one for each wheel of a 3-reel slot machine, for example. That number corresponds to a stop on one of the slot machine reels, and the reel will stop when that symbol or blank is in line with the payline. How does this process get affected by the fact that I'm spending more or less money on a spin? In other words, how do better combinations of payout symbols end up opposite the payout line when more money is spent on that spin?

The one explanation that occurred to me was that maybe the slot machine software can decrease the number of stops with an increase in the money spent per spin. In other words, a \$1 spin will have 32 stops per reel giving 32,768 possible combinations for a 3-reel machine, whereas a \$3 spin may be "adjusted" to have 24 stops per reel giving 13,824 possible combinations and therefore a slightly better chance of getting a more favourable set of payout symbols opposite the payout line.

Regards,
John

Dear John,

I think the key phrase in your letter is "seems to." Try an experiment. Play 1000 spins one coin at a time on a machine and count the number of hits you get. Do another 1000 spins playing three coins at a time. The number of hits you get should be very close each time. (Note that 1000 spins is the bare minimum needed to compare hit frequencies, so it might take another 1000 or more spins for the two numbers to converge.)

It's illegal in every jurisdiction with which I'm familiar for a slot program to take into account the number of coins played when determining which symbols will land on the payline. The number of virtual stops on each reel and the layout of the symbols on those virtual reels remain constant regardless of the number of coins played.

Now, it is possible to have a higher long-term payback when playing full coin, but that's just because some combinations pay more when you play full coin. Still, the chances of landing those combinations doesn't change when you increase your bet.

Best of luck in and out of the casinos! John

P.S. I went to the site you mentioned and Norton Anti-Virus said the page was infected with the Nimda virus. It may have been a false alarm, but you may want to use an anti-virus program to scan your PC to make sure you are not infected.

Hi John,

Thanx a million for replying....and so promptly as well!! Much appreciated.

By the way, I hail from Cape Town here in South Africa and we have only recently had casinos legalised, generally, in this country. The local casino has about 1700 slot machines and I tend to target only the 3-coin single line payouts. Virtually all the slot machines in the casino are either IGT or UNIVERSAL types which, I assume, have been purchased and imported from the USA. If, from what you say, it's illegal in your jurisdiction "for a slot program to take into account the number of coins played when determining which symbols will land on the payline," then I'm pretty sure the same criteria and controls would apply here, considering where the machines come from.

Based on what you say, I will in future play single coins now that I know that the outcome is not affected by the number of coins you insert! What you told me also confirms what I read in "Slot Smarts" by Claude Halcombe. His various "game plans" are also based on playing only one coin at a time. As a matter of interest, which book on slot playing strategy (which has the minimum of useless information about the history of slot machines etc..) would you recommend as the "best in the business"? I note that there is an offer at Amazon.com for both The Slot Machine Answer Book by John Grochowski and Break the One-Armed Bandits by Frank Scoblete. Any comments?

Yes, there does appear to be a virus on that web site. However, my anti-virus software sorted it and I got in with no problems after it quarantined the bug.

Regards,
John

Dear John,

Most of the gambling jurisdictions here in the United States modeled their rules on either Nevada's or New Jersey's or a combination of the two. I don't know what regulations apply in South Africa.

Nevada has a regulation that to be licensed in Nevada, all of the machines that a slot manufacturer makes, regardless of where the purchasing casino is located, must meet Nevada's regulations. I think it's safe to say that the number of coins played will not affect the symbols that land on the payline on an IGT machine.

I was able to download the e-book, even though the virus on the home page was a bit off-putting. The author does a good job of explaining how a modern slot machine works.

I recommend both The Slot Machine Answer Book and Break the One-Armed Bandits. And I also recommend my own The Slot Expert's Guide to Playing Slots, which will be available online (Amazon and www.greatstuff4gamblers.com) and at bookstores in about one month.

John

Send your slot and video poker questions to John Robison, Slot Expert, at slotexpert@comcast.net.

The Slot Expert's Guide to Playing Slots by John Robison
Break the One-Armed Bandits! by Frank Scoblete
Victory at Video Poker and Video Craps, Keno and Blackjack! by Frank Scoblete
Slot Conquest Audio Cassette Tape (60 minutes) with Frank Scoblete
Winning Strategies at Slots & Video Poker! Video tape hosted by Academy Award Winner James Coburn, Written by Frank Scoblete
The Slot Machine Answer Book by John Grochowski
The Video Poker Answer Book by John Grochowski
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