A shuffle through the gaming mailbag

Q. Does the house have an additional advantage when it utilizes shuffling machines?

A. Automatic shufflers don't add anything extra to the house edge. In fact, Michael Shackleford has written on his wizardofodds.com site that continuous shufflers, in which cards are shuffled back into the deck after they're played, actually decrease the house edge by a slight amount. The effect is small — about two-hundredths of a percent in a six-deck game.

However, automatic shufflers do speed up the games. More hands per hour are dealt, meaning the house edge has more chances to work against players, and the casino makes more money. The added speed of the game far outweighs that small decrease in house edge in games with continuous shufflers, which can add 10 or more hands per hour to the 50 or so played at a full seven-player table.

Beyond that, continuous shufflers make counting cards impossible. Even if you're not a card counter, continuous shufflers work against you because there are no breaks to change decks and cut the cards, meaning the games are faster than those using non-continuous machine shufflers.

If all other rules are equal, the best games for basic strategy players and average players are those that are hand-shuffled, yielding the fewest hands per hour. Next are regular machine-shuffled games where the cards are taken out of the machine and put into a shoe, and the worst games for players are those that use continuous shufflers. That's strictly because of speed of play and number of hands per hour exposed to the house edge.

Card counters want a faster game, with more hands per hour at which they have an edge on the casino. So they prefer regular machine-shuffled games, followed by hand-shuffled games, but do not play games that use a continuous shuffler.

Q. Every time I go to the casino, it seems I see the same lady playing two slot machines at once. Sometimes it's the quarter Wheel of Fortunes, sometimes it's Double Diamonds without the wheel, but it's always the same thing. She has credits on both machines, and while the reels are spinning on one machine, she taps the max coins button on the other, back and forth and back and forth.

I asked her one day why she did it, and she figured that if she played two machines right next to each other, at least one might be a hot machine. She thought she had a better chance of winning that way.

I have my doubts, so I'm asking you. Does it help to play more than one machine at once?

A. That's not an unusual method of playing slots, but no, I'm afraid it doesn't help to play more than one machine at once. That's not to say the player won't hit an occasional jackpot she wouldn't have hit if she was only playing one machine, but far more often the result of playing two machines at once is bigger, faster losses.

It's not as common as it once was to have machines with far different payback percentages next to each other. But even if there was a big disparity, playing side-by-side machines in hopes one is a big payer is a losing proposition.

Let's say that at two adjacent machines, one has programmed odds that will lead to return 89% in the long run, and the other to a 97% payback. I sit down at the 89-percenter and play 500 spins per hour — a steady but easy pace — betting three quarters on each spin. I risk $375 per hour, and on the average will lose $41.25. If instead I risk my $375 per hour on the machine set at 97%, my average hourly loss is only $11.25.

Clearly, if I play only one machine, I'm better off at the 97-percenter. Unfortunately, there is no way of telling which is which. So am I better off to play both machines, assuring that at least part of my play is on the 97-percent game? Well, if I wait until the reels stop on one machine to start the other and play the same total of 500 spins per hour, my average losses become $26.25 — better than playing just the 89-percenter, but worse than if blind luck takes me to the 97-percenter.

But that's not the way two-machine players handle things. They tend to do as you described, and hit the button on one while the reels are spinning on the other. That takes them very close to 500 spins per hour on each machine, so they not only lose the $41.25 per hour on the low-payer, but also lose the $11.25 per hour on the high-paying machine. Losses total $52.50 per hour. They're worse off, not better, playing two games at once.

Of course, on any slot machine, it's possible to either win big or lose fast in the short term. The woman who plays two machines at once will hit more jackpots than if she only played one, but that's simply because she's making more bets. She's taking more risk and losing more money in the long run.