Slot Machine Structural Characteristics: Creating Near Misses Using High Award Symbol Ratios

A near miss is a failure that was close to a win. In this paper we analyze the primary documents associated with a case that was brought before the Nevada Gaming Commission in 1988. This case resulted in the 1989 ruling that the proprietary computer algorithms used by one slot machine manufacturer to create a high number of near misses on the payline are “unacceptable,” whereas the use of virtual reel mapping to create near misses above and below the payline is acceptable. We show how, before and after 1989, slot machine manufacturers use virtual reels and a technique called “award symbol ratio” to create a high number of near misses above and below the payline and how this acceptable practice has the unintended effect of also creating near misses on the payline which can be explained by a software concept called feature interaction. The paper concludes with a discussion of the implications of near misses for problem gambling.