The priority heuristic is a simple, lexicographic decision strategy that helps decide for a good option.
Unfortunately, dissimilarity checks are often not decisive, and Rubinstein suggested that people proceed to a third step that he left unspecified.
This difference is larger than 10%, examination stops and people are correctly predicted to choose D because of its higher probability of winning.
The priority heuristic correctly predicted the majority choice in all (one-stage) gambles in Kahneman and Tversky (1979).
Across four different data sets with a total of 260 problems, the heuristic predicted the majority choice better than (a) cumulative prospect theory, (b) two other modifications of expected utility theory, and (c) ten well-known heuristics (such as minimax or equal-weight) did.