How can people who lack access to effective government institutions establish property rights and facilitate exchange? The illegal narcotics trade in Los Angeles has flourished despite its inability to rely on state-based formal institutions of governance. An alternative system of governance has emerged from an unexpected source—behind bars. The Mexican Mafia prison gang can extort drug dealers on the street because they wield substantial control over inmates in the county jail system and because drug dealers anticipate future incarceration. The gang's ability to extract resources creates incentives for them to provide governance institutions that mitigate market failures among Hispanic drug-dealing street gangs, including enforcing deals, protecting property rights, and adjudicating disputes. Evidence collected from federal indictments and other legal documents related to the Mexican Mafia prison gang and numerous street gangs supports this claim.

Candidates often make ambiguous statements about the policies they intend to pursue. In theory, ambiguity affects how voters make choices and who wins elections. In practice, measurement and endogeneity problems have impeded empirical research about the consequences of ambiguity. We conducted survey experiments that overcame these obstacles by manipulating a common form of ambiguity: the imprecision of candidate positions. Our data show that, on average, ambiguity does not repel and may, in fact, attract voters. In nonpartisan settings, voters who have neutral or positive attitudes toward risk, or who feel uncertain about their own policy preferences, tend to embrace ambiguity. In partisan settings, voters respond even more positively to ambiguity; they optimistically perceive the locations of ambiguous candidates from their own party without pessimistically perceiving the locations of vague candidates from the opposition. We further find, through analysis of two additional new data sets, that candidates often take—and voters frequently perceive—ambiguous positions like the ones in our experiments. The pervasive use of ambiguity in campaigns fits with our experimental finding that ambiguity can be a winning strategy, especially in partisan elections.

Do street-level bureaucrats discriminate in the services they provide to constituents? We use a field experiment to measure differential information provision about voting by local election administrators in the United States. We contact over 7,000 election officials in 48 states who are responsible for providing information to voters and implementing voter ID laws. We find that officials provide different information to potential voters of different putative ethnicities. Emails sent from Latino aliases are significantly less likely to receive any response from local election officials than non-Latino white aliases and receive responses of lower quality. This raises concerns about the effect of voter ID laws on access to the franchise and about bias in the provision of services by local bureaucrats more generally.

The infrequency of issue voting in American presidential elections is usually attributed to a lack of policy rationality among voters. An examination of the Vietnam war issue in 1968 suggests, however, that much of the explanation may lie instead with the electoral process itself, and with the kinds of choices which are offered to citizens.

Policy preferences concerning Vietnam were only weakly related to the two-party vote. Less than 2 per cent of the variance in voting choices between Nixon and Humphrey could be accounted for by opinions on Vietnam. Yet the absence of issue voting could not be fully explained by voters' failings. Most people had strong opinions about Vietnam. The public was generally able to perceive where prenomination candidates stood on the issue. People were able and willing to take account of Vietnam in evaluating other candidates.

Voters did not bring their Vietnam preferences to bear upon the choice between Nixon and Humphrey because they saw little difference between the positions of the two, and because they were not certain precisely where either one stood. These perceptions, in turn, were rooted in reality. Humphrey's and Nixon's campaign speeches show that they did differ rather little on specific proposals about Vietnam. Further, both candidates indulged in so much ambiguity about Vietnam that public confusion over their positions was understandable.

There are theoretical reasons for believing that candidates in a two-party system often have an incentive to converge at similar policy positions, and to be vague. If they generally do so, their behavior may contribute significantly to the apparent nonrationality of voters. In addition, it may have important implications for questions of collective rationality and social choice.

Despite the measured pace of American elections, there have now been a number of presidential campaigns since the advent of survey studies of voting. However sparingly, political history slowly has added to the set of distinct configurations of men and events which comprise a contest for the Presidency. The set is still small, whatever the impression created by massed thousands of interviews or by the accompanying files of election returns. Yet it is now large enough to be pressed hard for evidence about the sources of electoral change.

A primary virtue of measurements extended over a series of elections is that they can throw light on the problem of change. So long as the earliest voting studies were confined to cross-sectional relationships, they could deal only very inadequately with changes superimposed on these relationships or with changes in the relationships themselves. In the case of Lazarsfeld's enormously influential Erie County study in 1940, the natural limitations of a single-election study were compounded by the investigators' misfortune in choosing a campaign whose dominant personality and principal issues differed little from those of preceding elections. I have often wondered whether the static social determinism of The People's Choice would have emerged from a campaign in which the tides of short-term change were more nearly at flood.

I shall examine here some sources of change which are richly evident in the presidential elections of the last two decades.

We present experimental results on groups facing a decision problem analogous to that faced by a jury. We consider three treatment variables: group size (three or six), number of votes needed for conviction (majority or unanimity), and pre-vote deliberation. We find evidence of strategic voting under the unanimity rule: A large fraction of our subjects vote for a decision analogous to conviction even when their private information indicates a state analogous to innocence. This is roughly consistent with the game theoretic predictions of Feddersen and Pesendorfer. Although individual behavior is explained well by the game theoretic model, there are discrepancies at the level of the group decision. Contrary to Feddersen and Pesendorfer, in our experiments there are fewer outcomes analogous to incorrect convictions under unanimity rule than under majority rule. In the case of no deliberation, we simultaneously account for the individual and group data using quantal response equilibrium.

The argument is presented for defining party identification by the root question, “Generally speaking, do you usually think of yourself as a Republican, a Democrat, an independent, or what?” With this definitional base, the partisan balance between Democrats and Republicans between 1952 and 1980 shows no evidence of realignment outside the South, belying the implications of the Markus-Converse and Fiorina analyses that suggest volatility in response to short-term influences. It also appears that the correlation between party identification and voter choices for president are very constant over time in the South as well as outside the South. Party line voting by party identifiers varies by region and party but did not decrease between 1952 and 1988.

Political knowledge is a central concept in the study of public opinion and political behavior. Yet what the field collectively believes about this construct is based on dozens of studies using different indicators of knowledge. We identify two theoretically relevant dimensions: a temporal dimension that corresponds to the time when a fact was established and a topical dimension that relates to whether the fact is policy-specific or general. The resulting typology yields four types of knowledge questions. In an analysis of more than 300 knowledge items from late in the first decade of the 2000s, we examine whether classic findings regarding the predictors of knowledge withstand differences across types of questions. In the case of education and the mass media, the mechanisms for becoming informed operate differently across question types. However, differences in the levels of knowledge between men and women are robust, reinforcing the importance of including gender-relevant items in knowledge batteries.

The moral economic school, which has flourished among anthropologists, economic historians, and classicists, has received only limited attention from political scientists. This is perplexing, since at its core is to be found an intersection of debates over rational choice theory, the character of modern and premarket societies, and the normative standing of the market—in other words, over issues of formidable importance to our discipline. I seek to correct that neglect by mapping out and critically analyzing the moral economists' conception of modernity, their critique of the economic approach to human behavior and institutions, and their attempt to formulate an Aristotelian theory of the economy. These projects, though flawed, together are more than rich enough to provide fertile ground for political scientists and philosophers. I conclude with a discussion of the moral economists' effort to develop a normative theory of the economy together with a related critique of the market.

This article exploits variation between and within countries to examine the legacy of recorded conflicts in Africa in the precolonial period between 1400 and 1700. There are three main findings. First, we show that historical conflict is correlated with a greater prevalence of postcolonial conflict. Second, historical conflict is correlated with lower levels of trust, a stronger sense of ethnic identity, and a weaker sense of national identity across countries. Third, historical conflict is negatively correlated with subsequent patterns of development looking at the pattern across grid cells within countries.

I provide evidence that the degree to which medieval Hindus and Muslims could provide complementary, nonreplicable services and a mechanism to share the gains from exchange has resulted in a sustained legacy of ethnic tolerance in South Asian towns. Due to Muslim-specific advantages in Indian Ocean shipping, interethnic complementarities were strongest in medieval trading ports, leading to the development of institutional mechanisms that further supported interethnic exchange. Using novel town-level data spanning South Asia's medieval and colonial history, I find that medieval ports, despite being more ethnically mixed, were five times less prone to Hindu-Muslim riots between 1850 and 1950, two centuries after Europeans disrupted Muslim overseas trade dominance, and remained half as prone between 1950 and 1995. Household-level evidence suggests that these differences reflect local institutions that emerged to support interethnic medieval trade, continue to influence modern occupational choices and organizations, and substitute for State political incentives in supporting interethnic trust.

Richardson's finding that the severity of interstate wars is power law distributed belongs to the most striking empirical regularities in world politics. This is a regularity in search of a theory. Drawing on the principles of self-organized criticality, I propose an agent-based model of war and state formation that exhibits power-law regularities. The computational findings suggest that the scale-free behavior depends on a process of technological change that leads to contextually dependent, stochastic decisions to wage war.Early drafts of this paper were prepared for presentation at the University of Michigan, the University of Chicago, Ohio State University, Yale University, the University of Pennsylvania, and Cornell University. I am grateful to the participants in those meetings and to Robert Axelrod, Claudio Cioffi-Revilla, Fredrik Liljeros, and the editor and the anonymous reviewers of this journal for excellent comments. Laszlo Gulyas helped me reimplement the model in Java and Repast. Finally, I would like to acknowledge the generous support of the John M. Olin Institute for Strategic Studies. Nevertheless, I bear the full responsibility for any inaccuracies and omissions.

We analyze a model of a two-candidate election with costless voting in which voters have asymmetric information and diverse preferences. We demonstrate that a strictly positive fraction of the electorate will abstain and that, nevertheless, elections effectively aggregate voters' private information. Using examples, we show that more informed voters are more likely to vote than their less informed counterparts. Increasing the fraction of the electorate that is informed, however, may lead to higher levels of abstention. We conclude by showing that a biased distribution of information can lead to a biased voting population but does not lead to biased outcomes.

The literature on the democratic peace has emerged from two empirical claims: (1) Democracies are unlikely to conflict with one another, and (2) democracies are as prone to conflict with nondemocracies as nondemocracies are with one another. Together these assertions imply that the democratic peace is a dyadic phenomenon. There is strong support for the first observation, but much recent scholarship contravenes the second. This paper assesses whether the democratic peace is a purely dyadic, a monadic, or perhaps a mixed dyadic and monadic effect. Our analysis offers two important advances. First, our model directly compares the dyadic and monadic explanations by using the state as the unit of analysis rather than the potentially problematic dyad. Second, our model controls for an important but overlooked confounding variable: satisfaction with the status quo. Our results indicate that the initiation of violence within crises is predominantly a dyadic phenomenon, but we also find evidence suggesting a strong monadic effect regarding the emergence of crises.

Survey data regularly show that assessments of current and expected future economic performance are more positive when a respondent's partisanship matches that of the president. To determine if this is a survey artifact or something deeper, we investigate whether partisanship is associated with behavioral differences in economic decisions. We construct a new data set of county-level quarterly taxable sales to examine the effect of partisanship on consumption. Consumption change following a presidential election is correlated with a county's partisan complexion, a result consistent with partisans acting outside the domain of politics in accordance with the opinions they express in surveys. These results support an expansive view of the role of partisanship in mass politics and help validate surveys as a method for studying political behavior.

Although normative questions about the role of the Supreme Court as a countermajoritarian institution have long excited controversy in democratic theory, empirical questions about how far the Court acts contrary to majoritarian opinion have received less attention. Time series analyses for the period 1956–89 indicate the existence of a reciprocal and positive relationship between long-term trends in aggregate public opinion and the Court's collective decisions. The Court's ideological composition changes in response to previous shifts in the partisan and ideological orientation of the president and Congress. The Court also responds to public opinion at the margins even in the absence of membership change. Since 1981, the relationship has vanished or turned negative in direction. The Court's ideological balance has been upset by an unbroken string of conservative-to-moderate appointments, thereby undermining the dynamics that promote judicial responsiveness and raising questions about the majoritarianism of the contemporary and future Court.

We present a model of war duration which incorporates both realpolitik and domestic political variables. We hypothesize that strategy, terrain, capabilities, and government type, among other variables, will play key roles in determining the duration of war. We test these hypotheses using hazard analysis and find empirical support for our key arguments. We find that the realpolitik variables play a greater role than regime behavior and type in determining war duration. We also find that historically, on average, mobilization and strategic surprise have little effect on war duration and that wars are not duration dependent.

Based on survey responses from a national random sample of nearly 4,000 high school and college students, we uncover a dramatic gender gap in political ambition. This finding serves as striking evidence that the gap is present well before women and men enter the professions from which most candidates emerge. We then use political socialization—which we gauge through a myriad of socializing agents and early life experiences—as a lens through which to explain the individual-level differences we uncover. Our analysis reveals that parental encouragement, politicized educational and peer experiences, participation in competitive activities, and a sense of self-confidence propel young people's interest in running for office. But on each of these dimensions, women, particularly once they are in college, are at a disadvantage. By identifying when and why gender differences in interest in running for office materialize, we begin to uncover the origins of the gender gap in political ambition. Taken together, our results suggest that concerns about substantive and symbolic representation will likely persist.

Does social protest following the police killing of unarmed Black civilians have a widespread “opinion-mobilizing” effect against the police? Or, does the racialized nature of these events polarize mass opinion based on standing racial and political orientations? To answer these questions, we use a large dataset comprised of weekly cross sections of the American public and employ a regression discontinuity in time (RDiT) approach leveraging the random timing of the police killing of George Floyd and ensuing nationwide protests. We find that the Floyd protests swiftly decreased favorability toward the police and increased perceived anti-Black discrimination among low-prejudice and politically liberal Americans. However, attitudes among high-prejudice and politically conservative Americans either remained unchanged or evinced only small and ephemeral shifts. Our evidence suggests that the Floyd protests served to further racialize and politicize attitudes within the domain of race and law enforcement in the U.S.

How does the U.S. Supreme Court reach decisions? Since the 1940s, scholars have focused on two distinct explanations. The legal model suggests that the rule of law (stare decisis) is the key determinant. The extralegal model posits that an array of sociological, psychological, and political factors produce judicial outcomes. To determine which model better accounted for judicial decisions, we used Supreme Court cases involving the imposition of the death penalty since 1972 and estimated and evaluated the models' success in accounting for decisional outcomes. Although both models performed quite satisfactorily, they possessed disturbing weaknesses. The legal perspective overpredicted liberal outcomes, the extralegal model conservative ones. Given these results, we tested another proposition, namely that extralegal and legal frameworks present codependent, not mutually exclusive, explanations of decision making. Based on these results, we offer an integrated model of Supreme Court decision making that contemplates a range of political and environmental forces and doctrinal constraints.