Professor Andrew Gelman and Nate Silver discussed their findings on close elections in the House of Representatives in The New York Times Sunday, April 19. Gelman and Silver observe that "Although 'wave' elections like 1994 and 2006, in which a relatively high number of incumbents are unseated, can deliver momentarily higher numbers of close contests, the trend has generally been toward less competition. Indeed, it may be precisely because close Congressional races are so atypical that the exceptions get so much attention." The authors cite three possible reasons why there are fewer closer elections than there once were: powerful incumbents, self-sorting voters, and inflexible parties.