# The Mathematics Of… Shuffling

### from the ain't-so-random dept

dsg writes in with a link to a great article about some researchers who were asked by casinos to look at whether or not card shuffling machines really shuffled the cards randomly. They actually determined that a card counter who understood how those machines worked could double or even triple their odds. The advantage goes away, though, if they run the cards through the machine twice, which I imagine all casinos now do.

Joe Schmoe says:

# Wouldn't...

Wouldn’t simply cutting the deck before you place it in the machine be equally effective?

Anonymous Coward says:

# Re: Wouldn't...

This zig-zag pattern that they observed isn’t really changed by cutting the deck. You’ll find it more difficult to predict the top card, but knowing this zig-zag idea will still make prediction easier than a totally random deck.

cardman says:

# Re: Re: Wouldn't...

cutting the cards has real effect on the ordering of cards if you know the pattern. There are loads of conjuring tricks based on this – people assume that cutting the cards is a useful thing to do. In the long run it isn’t.

says: