Equilibrium Outcomes in Two-Stage Amendment Procedures

This paper analyzes the set of sophisticated voting outcomes under the following two-stage amendment procedure: the set of alternatives is partitioned into two subsets; one subset is voted on via an amendment procedure at the first stage, followed by the remaining subset at the second stage. The surviving alternatives are then paired at the final vote. This procedure is related to that used in congressional decision making when both a bill and a substitute bill are in order on the floor and hence are open to amendments. It is shown that it is "easier" for alternatives initially considered at the second stage to be the outcome of the voting game than those considered at the first stage. The set of outcomes is contrasted with that generated by the (one-stage) amendment procedure as well as the concept of the uncovered set