Slots and the limits of human reasoning

Related to this belief is the view that all random events should look “random,” and therefore people underestimate the chances of repeated numbers, sequences, or other patterns occurring.

Faced with unusual events such as 10 heads in a row, many people will believe either that the coin has a bias (i.e., bet on heads) or that the coin will now start to show a string of extra tails to balance itself out (i.e., bet on tails).

Often these errors are due to a misunderstanding of the nature of long-term outcomes.

From interviews with gamblers, it is clear that many people conceive of the long term as some definite time in the future (e.g., a million flips of the coin) by which the number of heads and tails will have balanced itself out.

In reality, the time frame is infinite.

In addition, the coin is not balanced out in the long term, but short-term deviation from the expected average gradually becomes watered down.

Suppose the first 100 flips of the coin were all heads and then the next 999,900 were perfectly balanced between heads and tails. The initial 100 heads might still be there, but, by the one millionth flip, the difference of 100 would hardly be noticeable. In fact, 3000 more heads than tails would still round off to 50% heads and 50% tails. The difference between heads and tails is not corrected at all, but that difference becomes less noticeable in the long term.

Many of the features of slots are poorly understood by problem gamblers, at-risk players, and treatment providers. Therefore, I believe that it is vitally important to understand how the machines work in order to set up effective treatment and prevention programs. However, in considering the nature of slots, we must keep in mind that misunderstanding of randomness is not unique to slots but is a general feature of gambling.