This paper uses the rank-dependent expected utility (RDEU) model to capture the effects of optimism and pessimism on the choice between a pre-trial settlement and a trial (or more generally, between a private settlement and a litigation). These two legal procedures are described as a bargaining game and a contest game, respectively. My models predict that a contest occurs if the aggregate optimism premium in a contest (AOPC) is sufficiently high. I also find that the AOPC tends to be higher for close cases. Such predictions are consistent with the Priest-Klein empirical observation that a plaintiff's winning probability is often near 50% in many areas of civil litigation. I also show that the highest levels of effort in both a bargaining game and a contest game are exerted when one is moderately optimistic. However, excessive optimism will reduce one's effort level, and hence, one's winning rate. As a result, when faced with an excessively optimistic party, a risk-neutral party may prefer a contest over bargaining.

本文使用基于等级的期望效用（RDEU）模型来捕捉乐观和悲观主义对审前和解与审判（或更笼统地说，在私人和解与诉讼之间）选择的影响。这两个法律程序分别称为讨价还价游戏和竞赛游戏。我的模型预测，如果比赛中的总体乐观溢价（AOPC）足够高，则会发生比赛。我也发现AOPC在接近的情况下往往更高。这样的预测与Priest-Klein的经验观察一致，即在许多民事诉讼领域中，原告的获胜概率通常接近50％。我还表明，在适度乐观的情况下，无论是在讨价还价游戏还是竞赛游戏中，都将付出最大的努力。但是，过于乐观会降低一个人的努力水平，从而降低其获胜率。结果，当面对过于乐观的政党时，风险中立的政党可能更喜欢竞争而不是讨价还价。