Whether referendums, initiatives, and other mechanisms of direct democracy enhance representative systems is a matter of debate. Skeptics note—among other criticisms—that turnout tends to be low in referendums, often lower than in candidate elections in the same country. If citizens do not care enough to participate, how useful can these mechanisms be for improving the quality of democratic systems? We argue that low referendum turnout has as much to do with parties’ disincentives to mobilize voters as it does with voter disinterest. Prior research on political behavior in referendums has focused largely on Europe and assumes that voters view them as elections of lesser importance. By shifting focus to Latin America, we introduce more variation in the features of political parties that influence levels of turnout. We draw on cross-national evidence, qualitative research in Colombia, and quantitative analysis of municipal-level referendum voting behavior in Brazil. The key to understanding low voter turnout in these settings is the relatively weaker incentives that political parties have to turn out the vote when control over office is not at stake. We demonstrate that, in clientelistic systems, party operatives have particularly weak incentives to get their constituents out to the polls.

Six patents were secured by E. H. Lanier from 1930 to 1933 for aeroplane designs that were intended to be exceptionally stable. A feature of five of these was a flow-induced “vacuum chamber” which was thought to provide superior stability and increased lift compared to typical wing designs. Initially, this chamber was in the fuselage, but later designs placed it in the wing by replacing a section of the upper skin of the wing with a series of angled slats. We report upon an investigation of the Lanier wing design using inviscid aerodynamic theory and viscous numerical simulations. This took place at the 2005 Australia–New Zealand Mathematics-in-Industry Study Group. The evidence from this investigation does not support the claims but, rather, suggests that any improvement in lift and/or stability seen in the few prototypes that were built was, most probably, due to thicker airfoils than were typical at the time.

In the early 1970s, Wayne Cornelius asked, “Are the migrant masses revolutionary? Definitely not, at least in Latin America and many other parts of the developing world.” These words summarized an emerging revisionist view of the political character of Latin America's new urban poor. Careful empirical research had proved wrong previous scholars and observers who had expected the new migrant populations in Latin America's cities to become sources of support for revolutionary political movements. A new picture of the inhabitants of Latin America's burgeoning shantytowns came into focus, showing these populations to be either passive or loyally engaged in the surrounding political system. According to this picture, squatters held considerable hope for individual advancement, forged clientelistic ties with government officials, and showed few signs of joining radicalized, class-conscious social movements.

We analyze vote buying in Argentina—the payment by political parties of minor benefits (food, clothing, cash) to citizens in exchange for their votes. How widespread is vote buying in Argentina, and what is the profile of the typical vote “seller”? Did the shift toward a neoliberal economic model in the 1990s increase or reduce vote buying? Why do parties attempt to buy votes when the ballot is secret and people could simply accept campaign handouts and then vote as they wish? We analyze responses to surveys we conducted in Argentina in 2002 and offer answers to these questions. Our findings suggest that vote buying is an effective strategy for mobilizing electoral support among low-income people when parties are able to monitor voters' actions, make reasonably accurate inferences about how individuals voted, and credibly threaten to punish voters who defect from the implicit clientelist bargain. Our results point toward ballot reform as one way to reduce vote buying in Argentina.

To what extent has the Argentine party system been polarized along class lines? The political historiography gives mixed and contradictory answers to this question. We explore the social bases of Argentina's political parties using an original database, the most comprehensive database of Argentine elections yet assembled, and new methods of ecological inference that yield more reliable results than previous analyses. We identify two distinct party systems, one in place between 1912 and 1940, the other emerging after 1946. The first party system was not consistently class based, but the second was, with the Radical Party representing the middle classes and the Peronists, workers and the poor. Still, there were important exceptions. Lower-class support for the Peronists, as proxied by literacy rates, declined during Perón's exile, which implies that the party had trouble mobilizing lower-class illiterate voters. Since the return to democracy in 1983, class polarization has again found some expression in the party system.

When a party or candidate loses the popular vote but still wins the election, do voters view the winner as legitimate? This scenario, known as an electoral inversion, describes the winners of two of the last six presidential elections in the United States. We report results from two experiments testing the effect of inversions on democratic legitimacy in the US context. Our results indicate that inversions significantly decrease the perceived legitimacy of winning candidates. Strikingly, this effect does not vary with the margin by which the winner loses the popular vote, nor by whether the candidate benefiting from the inversion is a co-partisan. The effect is driven by Democrats, who punish inversions regardless of candidate partisanship; few effects are observed among Republicans. These results suggest that the experience of inversions increases sensitivity to such outcomes among supporters of the losing party.

Congress hears more and more from everyday citizens. How do modern Congressional offices use this information to represent their constituents? Drawing on original interviews and a survey of Congressional staff, we explore how representation works in practice when new data and tools, such as databases and downscaled public opinion polls, are available. In contrast with established theories that focus on responsiveness, we show that representation is a two-way street. Congressional offices both respond to incoming constituent opinion and reach out to elicit opinions from stakeholders. Offices record correspondence into databases, identifying the most salient issues and the balance of opinion among correspondents. They tend not to use polls on policy. To understand the opinions of electorally influential constituencies, staffers also proactively reach out to stakeholders and experts in a practice we call provoked petitioning. If the Washington pressure system is a chorus, Congressional staff often serve as conductors, allowing well-resourced and organized constituents, including interest groups, to sing with the loudest voices. While Congress has some new tools and strategies for representation, its modern practices still reinforce existing biases.

Evolving conditions at the terminus of Thwaites Glacier will be important in determining the rate of its future sea-level contribution over the coming decades. Here, we use remote-sensing observations to investigate recent changes (2000–2018) in the structure and velocity of Thwaites Glacier and its floating tongue. We show that the main trunk of Thwaites Glacier has accelerated by 38% over this period, while its previously intact floating tongue has transitioned to a weaker mélange of fractured icebergs bounded by sea ice. However, the rate of structural weakening and acceleration was not uniform across the observational period and we identify two periods of rapid acceleration and structural weakening (2006–2012; 2016–2018), separated by a period of deceleration and re-advance of the structurally-intact shear margin boundary (2012–2015). The timing of these accelerations/decelerations strongly suggests a link to variable ocean forcing. The weakened tongue now has some dependency on landfast sea ice for structural integrity and is vulnerable to changes in landfast ice persistency. Future reductions in landfast sea ice could manifest from changes in climate and/or the imminent removal of the B-22A iceberg from the Thwaites embayment. Such changes could have important implications for the integrity of the ice tongue and future glacier discharge.

Small mountain glaciers are an important part of the cryosphere and tend to respond rapidly to climate warming. Historically, mapping very small glaciers (generally considered to be <0.5 km2) using satellite imagery has often been subjective due to the difficulty in differentiating them from perennial snowpatches. For this reason, most scientists implement minimum size-thresholds (typically 0.01–0.05 km2). Here, we compare the ability of different remote-sensing approaches to identify and map very small glaciers on imagery of varying spatial resolutions (30–0.25 m) and investigate how operator subjectivity influences the results. Based on this analysis, we support the use of a minimum size-threshold of 0.01 km2 for imagery with coarse to medium spatial resolution (30–10 m). However, when mapping on high-resolution imagery (<1 m) with minimal seasonal snow cover, glaciers <0.05 km2 and even <0.01 km2 are readily identifiable and using a minimum threshold may be inappropriate. For these cases, we develop a set of criteria to enable the identification of very small glaciers and classify them as certain, probable or possible. This should facilitate a more consistent approach to identifying and mapping very small glaciers on high-resolution imagery, helping to produce more comprehensive and accurate glacier inventories.