摘要：It has been argued that close elections lead to policy convergence, as legislators elected by a small margin are more likely to adopt moderate policy positions (Downs 1957). However, Lee, Moretti, and Butler (2004) find that electoral competition does not affect legislators’ policy preferences in the United States, questioning the median voter paradigm. To help to discern this paradox, we estimate the effect of close elections on legislators’ subsequent policy positions under different electoral rules. With Chile’s two-seat open-list proportional representa-tion system, we exploit the dynamics of within-coalition competition to test both hypotheses. Using the margin of victory in 383 races in four different parliamentary elections and 3,741 roll-call votes for the 120-seat Chamber of Deputies from 1998 to 2014, we find that electoral competition did not lead to policy convergence under either the center-left Concertación coalition or the rightist Alianza coalition. We contend that policy convergence responds to electoral incentives but is also conditioned by the nature of the political regime (presidential or parliamentary) and government–opposition dynamics.
关键词：Chile;regression discontinuity design;legislative preferences;electoral systems
