1

Paper

Extracting Systematic Social Science Meaning from Text Hopkins, Daniel King, Gary Uploaded 07-12-2007 Keywords automated content analysis machine learning simulated extrapolation non-parametric estimation internet 2008 U.S. Presidential election Abstract We develop two methods of automated content analysis that give approximately unbiased estimates of quantities of theoretical interest to social scientists. With a small sample of documents hand coded into investigator-chosen categories, our methods can give accurate estimates of the proportion of text documents in each category in a larger population. Existing methods successful at maximizing the percent of documents correctly classified allow for the possibility of substantial estimation bias in the category proportions of interest. Our first approach corrects this bias for any existing classifier, with no additional assumptions. Our second method estimates the proportions without the intermediate step of individual document classification, and thereby greatly reduces the required assumptions. For both methods, we also correct statistically, apparently for the first time, for the far less-than-perfect levels of inter-coder reliability that typically characterize human attempts to classify documents, an approach that will normally outperform even population hand coding when that is feasible. We illustrate these methods by tracking the daily opinions of millions of people about candidates for the 2008 presidential nominations in online blogs, data we introduce and make available with this article, and through evaluations in available corpora from other areas, including movie reviews, university web sites, and Enron emails. We also offer easy-to-use software that implements all methods described.

2

Paper

The Most Liberal Senator: Analyzing and Interpreting Congressional Roll Calls Clinton, Joshua Jackman, Simon Rivers, Doug Uploaded 05-12-2004 Keywords ideal points roll call voting 2004 presidential election Abstract The non-partisan National Journal recently declared Senator John Kerry to be the "top liberal" in the Senate based on analysis of 62 roll calls in 2003. Although widely reported in the media (and the subject of a debate among the Democratic presidential candidates), we argue that this characterization of Kerry is misleading in at least two respects. First, when we account for the "margin of error: in the voting scores -- which is considerable for Kerry given that he missed 60% of the National Journal's key votes while campaigning -- we discover that the probability that Kerry is the "top liberal" is only .30, and that we cannot reject the conclusion that Kerry is only the 20th most liberal senator. Second, we compare the position of the President Bush on these key votes; including the President's announced positions on these votes reveals the President to be just as conservative as Kerry is liberal (i.e., both candidates are extreme relative to the 108th Senate). A similar conclusion holds when we replicate the analysis using all votes cast in the 107th Senate. A more comprehensive analysis than that undertaken by National Journal (including an accounting of the margins of error in voting scores) shows although Kerry belongs to the most liberal quintile of the contemporary Senate, Bush belongs to the most conservative quintile.

3

Paper

Spatial Voting Theory and Counterfactual Inference: John C. Breckenridge and the Presidential Election of 1860 Jenkins, Jeffery A. Morris, Irwin Uploaded 07-02-2003 Keywords spatial voting theory counterfactual inference presidential election Abstract One important catalyst for the onset of the Civil War was the presidential election of Abraham Lincoln in 1860. Lincoln, competing against three other candidates, won election with the smallest percentage of the popular vote in American history. Given the circumstances, a slightly different electoral slate might have engineered his defeat. We examine this possibility by focusing on the candidacy of John C. Breckinridge, the final entrant into the race. Historians disagree over the rationale behind Breckinridge's candidacy. Some argue that it was a desperate effort to defeat Lincoln; others suggest that it was designed to insure Lincoln's victory. Using election counterfactuals and applying spatial voting theory, we examine these arguments. Our evidence suggests that Breckinridge had no reasonable chance to win. Support for Breckinridge's candidacy was only reasonable if the intention were to elect Lincoln.

4

Paper

Did Illegally Counted Overseas Absentee Ballots Decide the 2000 U.S. Presidential Election? Imai, Kosuke King, Gary Uploaded 02-13-2002 Keywords 2000 U.S. Presidential Election Ecological Inference Bayesian Model Averaging Abstract Although not widely known until much later, Al Gore received 202 more votes than George W. Bush on election day in Florida. George W. Bush is president because he overcame his election day deficit with overseas absentee ballots that arrived and were counted after election day. In the final official tally, Bush received 537 more votes than Gore. These numbers are taken from the official results released by the Florida Secretary of State's office and so do not reflect overvotes, undervotes, unsuccessful litigation, butterfly ballot problems, recounts that might have been allowed but were not, or any other hypothetical divergence between voter preferences and counted votes. After the election, the New York Times conducted a six month long investigation and found that 680 of the overseas absentee ballots were illegally counted, and no partisan, pundit, or academic has publicly disagreed with their assessment. In this paper, we describe the statistical procedures we developed and implemented for the Times to ascertain whether disqualifying these 680 ballots would have changed the outcome of the election. The methods involve adding formal Bayesian model averaging procedures to King's (1997) ecological inference model. Formal Bayesian model averaging has not been used in political science but is especially useful when substantive conclusions depend heavily on apparently minor but indefensible model choices, when model generalization is not feasible, and when potential critics are more partisan than academic. We show how we derived the results for the Times so that other scholars can use these methods to make ecological inferences for other purposes. We also present a variety of new empirical results that delineate the precise conditions under which Al Gore would have been elected president, and offer new evidence of the striking effectiveness of the Republican effort to convince local election officials to count invalid ballots in Bush counties and not count them in Gore counties.

5

Paper

Detection of Multinomial Voting Irregularities Mebane, Walter R. Sekhon, Jasjeet Wand, Jonathan Uploaded 07-17-2001 Keywords outlier detection robust estimation overdispersed multinomial generalized linear model 2000 presidential election voting irregularities Abstract We develop a robust estimator for an overdispersed multinomial regression model that we use to detect vote count outliers in the 2000 presidential election. The count vector we model contains vote totals for five candidate categories: Buchanan, Bush, Gore, Nader and ``other.'' We estimate the multinomial model using county-level data from Florida. In Florida, the model produces results for Buchanan that are essentially the same as in a binomial model: Palm Beach County has the largest positive residual for Buchanan. The multinomial model shows additional large discrepancies that almost always hurt Gore or Nader and help Bush or Buchanan.

6

Paper

The Foundations of Latino Voter Partisanship Alvarez, R. Michael Bedolla, Lisa Garcia Uploaded 03-08-2001 Keywords Latino Partisanship 2000 presidential election Abstract Traditionally, the Latino electorate has been considered to be Democratic in partisan affiliation. However, during the 2000 presidential election there were many efforts made by the Republican party to court Latino voters, suggesting that perhaps Latino voters may becoming more Republican in orientation. Using a telephone survey of Latino likely voters conducted in the 2000 election, we examine three different sets of correlates of Latino voter partisanship: social and demographic, issue and ideological, and economic. We find that in Latino voter partisanship is strongly structured by social and demographic, as well as issue and ideological, factors. We also find that while it is unlikely that changes in economic factors or abortion attitudes will significantly change which parties the different Latino nation-origin groups identify with, it is possible that changes in ideological positoins regarding the role of government in providing social services could result in significant changes in Latino party identification.

7

Paper

Do Voters Learn from Presidential Election Campaigns? Alvarez, R. Michael Glasgow, Garrett Uploaded 10-27-1997 Keywords random effects panel models content analysis presidential election campaigns voter decisionmaking voter learning Abstract We present a model of voter campaign learning which is based on Bayesian learning models. This model assumes voters are imperfectly informed and that they incorporate new information into their existing perceptions about candidate issue positions in a systematic manner. Additional information made available to voters about candidate issue positions during the course of a political campaign will lead voters to have more precise perceptions of the issue positions of the candidates involved. We use panel survey data from the 1976 and 1980 presidental elections, combined with content analyses of the media during these same elections. Our primary analysis is conducted using random effects panel models. We find that during each of these campaigns many voters became better informed about the positions of candidates on many issues and that these changes in voter information are directly related to the information flow during each presidential campaign.

8

Paper

Should the Democrats move to the left on economic policy? Gelman, Andrew Uploaded 09-20-2006 Keywords median voter Presidential election public opinion spatial model of voting Abstract Could John Kerry have gained votes in the recent Presidential election by more clearly distinguishing himself from George Bush on economic policy? At first thought, the logic of political preferences would suggest not: the Republicans are to the right of most Americans on economic policy, and so in a one-dimensional space with party positions measured with no error, the optimal strategy for the Democrats would be to stand infinitesimally to the left of the Republicans. The median voter theorem suggests that each party should keep its policy positions just barely distinguishable from the opposition. In a multidimensional setting, however, or when voters vary in their perceptions of the parties' positions, a party can benefit from putting some daylight between itself and the other party on an issue where it has a public-opinion advantage (such as economic policy for the Democrats). We set up a plausible theoretical model in which the Democrats could achieve a net gain in votes by moving to the left on economic policy, given the parties' positions on a range of issue dimensions. We then evaluate this model based on survey data on voters' perceptions of their own positions and those of the candidates in 2004. Under our model, it turns out to be optimal for the Democrats to move slightly to the {em right} but staying clearly to the left of the Republicans' current position on economic issues.