1. In a system for the adaptive reordering of sequential decisions in the search of a data base so that the average time to execute the decisions is minimized, said system including computing means for computing each decision the ratio p/c where p is the probability of a successful outcome of the decision and c is the cost of computation to make that decision, said computing means comprising: means for estimating the logarithms of the probability p and the cost c for each decision; means for subtracting the logarithm c from the logarithm p to produce a ratio of p/c for each decision; means for comparing the ratios of p/c to produce a priority value for each decision; and means for reordering said decisions based on the priority value assigned to each decision.