1. Nonswitchers drop from the main specification of equation (5) by construction via differences.
2. Again, similar patterns hold when estimating a LAD regression, although the coefficients are slightly smaller and the standard errors larger.
3. Another approach to eliminating the influence of outliers is to conduct a nonparametric sign test evaluating the pattern of results displayed in Fig. 7. We tested whether the observations were more likely to fall in quadrants I and III as opposed to the null of an equal distribution. We find that 31 of the 53 observations are in these two quadrants and reject the null of a homogenous distribution at p = .136. For the alternative specification (see Section 6.1), 33 of the 53 observations are in these two quadrants and we reject the null of a homogenous distribution at p = .049.
4. These values come from the R-squared of a regression of actual changes in the number of representatives on deserved changes in the number of representatives based on a simulated Congress that awards fractional seats
5. In practice, the common divisor must be modified slightly to ensure that the size of the House remains exactly 435 after rounding.