The Baccy Bandit (known in a previous incarnation as the One Armed Bandit) is a game in the Prancing Spiderkitty. CavemanJoe once said:

Okay so some tips for the bandit.
The bandit is modelled on a hybrid percentaging system, a mix of the American and British approach.
The American approach is to arrange the symbols on the reels in whatever order will give the desired payout - I decided I wanted a 90% payout, which is better than you'll get from any real-life machine.
In an American game, you spin the wheels and it's entirely random what happens.
Percentaging is tested by running a million or so plays through the machine and then rearranging the reels to adjust it up or down and then continually testing it until it's about right.
Now British fruities are completely different.
British fruities decide whether you win or lose before you even put your money in, and there's nothing random about them at all. When their actual payout percentage is lower than desired, it pays out more, and vice versa.
So the whole gamblers-fallacy thing, where people think “It's not paid out in ages, it must be due to pay out soon” - on British fruit machines, that's not a fallacy. They're won by watching people play them in the pub…
…and jumping in when they've not had a big payout in a while.
To Americans, our fruities must seem like a horrible scam. To Brits, American bandits seem boring as fuck to play.
So, the Island's bandit uses both of these methods.
What actually comes up on the reels is truly random, and you have the same odds from game to game.
However, the hold and nudge features are percentaged dynamically.
The machine keeps track of how much has gone in and how much has come out, and if it's not paying out enough, it'll give more Holds and Nudges.
So you can get a rough idea of what sort of mood the machine's in by looking at how often you get holds and nudges, and base your gambling decisions on that information. :)