Evaluation results by subjective evaluation method in usability test is depends on a participant's memory.
Therefore there is leaked information from evaluation result. We propose pair-testing for reducing leaked information.
In the method, a participant and an evaluator record participant’s evaluation and confirm together. Proposal method experimentally applied behavior analysis of a tourist. And we analyzed reduction effect of leaked information by complement. From the analysis result, 45.7% of participants’ evaluation is complemented by recorded evaluation of evaluators.