The role of an expert in the decision-making process is crucial, as the final recommendation depends on his disposition, clarity of mind, experience, and knowledge of the problem. However, the recommendation also depends on their honesty. But what if the expert is dishonest? Then, the answer on how difficult it is to manipulate in a given case becomes essential. In the presented work, we consider manipulation of a ranking obtained by comparing alternatives in pairs. More specifically, we propose an algorithm for finding an almost optimal way to swap the positions of two selected alternatives. Thanks to this, it is possible to determine how difficult such manipulation is in a given case. Theoretical considerations are illustrated by a practical example.

翻译：专家在决策过程中起着至关重要的作用，因为最终建议取决于其倾向、思维清晰度、经验及对问题的了解。然而，建议也取决于其诚实性。但若专家不诚实，那么回答特定情形下操纵的难易程度就变得至关重要。本文考虑对通过成对比较备选方案而获得的排序进行操纵。具体而言，我们提出了一种算法，用于以近乎最优的方式交换两个选定备选方案的位置。由此，可确定此类操纵在特定情形下的难易程度。理论分析通过一个实际案例加以说明。