A Sequential Sensitivity Analysis was performed for same–different tests using low-concentration threshold NaCl solutions versus purified water. The order of favorability for the sequence pairs (W-S, W-W, S-S, S-W) was different from the order obtained in previous studies (W-S, S-W, W-W, S-W). In the current study, the order depended on the judge's ability to recognize perceptual changes; this could be said to involve a decision rule or cognitive strategy that used a τ criterion. In previous studies, the orders depended on the judges’ ability to recognize individual stimuli; this could be said to involve a decision rule that used a β criterion. Further insights into the interpretation of these orders were discussed.