A q-rule is where a winning coalition has q or more of the n voters. An important issue is to understand when, generically, core points exist; that is, to determine when the core exists in other than highly contrived settings. As known, the answer depends upon the dimension of issue space....

Following the recent turn towards quasi-experimental approaches in the US literature on the incumbency advantage (Lee, 2001; Lee, forthcoming), we employ a Regression Discontinuity Design (RDD) to identify the causal effects of party incumbency in British and German post-World War II elections. The...