We define a family of runoff rules that work as follows: voters cast approval ballots over candidates; two finalists are selected; and the winner is decided by majority. With approval-type ballots, there are various ways to select the finalists. We leverage known approval-based committee rules and study the obtained runoff rules from an axiomatic point of view. Then we analyze the outcome of these rules on single-peaked profiles, and on real data.

翻译：我们定义了一类决选规则族，其运行方式如下：选民对候选人投批准票；选出两名决赛者；获胜者由多数决决定。在批准型选票下，有多种选择决赛者的方式。我们利用已知的基于批准的委员会规则，并从公理化的角度研究所得决选规则。随后，我们在单峰分布上以及真实数据中分析了这些规则的结果。