Slot Machine Strategies

How They Work

Slot machines are one of the most misunderstood forms of gambling in the casinos.

Many books on slot machines incorrectly state that each reel is equally likely to stop on each position, or stop. They reason that if a slot machine has 22 stops on each reel and one jackpot symbol on each reel, then the probability of hitting the jackpot is 1 in 223 = 1/10648. This was true of the early days of slot machines before they become electronic, and of multi-line machines. However this is not true of single line machines, which most slot machines are. The fact is that on single line machine each stop is electronically weighted and the probability of the reel stopping on each symbol is proportional to its weight.

Following is a detailed explanation of how modern single-line slot machines work:

1. Player initiates a new play by inserting a coin, pulling the handle, or hitting the 'spin' button.
   
   
2. The machine selects three random numbers. These are chosen from a random number generator that is constantly drawing random numbers at a rate of thousands per second. The numbers chosen at the moment the play is initiated are the ones used to determine the final outcome. In other words the outcome is predestined the moment you spin the reels.
   
   
3. The raw three random numbers chosen from the previous step will usually be very large, very small is also a possibility. These numbers will be converted to a desired range, for example integers from 0 to 63. An easy way this can be done is to divide the large number by the desired number and taking the remainder.
   
   
4. The small random numbers will go through a mapping table to be assigned a specific reel to stop on. Each possible random number on each reel is mapped to a specific stop. Generally the higher paying symbols are mapped to fewer numbers.
   
   
5. Almost instantly after the player presses spin the machine has determined where the reels are going to stop. It then lets them spin a few seconds for entertainment value and then will exactly where programmed to.
   Multi-line slots, both with physical as well as video display reels usually do not have weighted reels. Otherwise the process is the same as above. In video display slots representations of actual reels are used, which can be quite large, 60 symbols or more.

Variable State Slots

Some of the video display slot machines have a feature in which a bonus rises the more the player plays it. When the reels stop in a particular configuration the player wins the coins in the meter. These kinds of slots have variable states. In other words the higher the state the greater the expected payback. Examples of this kind of machine include Piggy Bank, Car Race, Temperature Rising, and Double Diamond Mine.

It is possible to have a positive expected value playing slots if you only play variable state slots in very high states. Sometimes casual players will walk away from a machine in a high state. However this secret is long since out and competition for these games can be severe, fistfights have been known to occur over them.

Myths about Slot Machines

How Slots Work

Miscellaneous Tips

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