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Incentivized experiments are frequently used to learn about individuals’ social, political, and economic behavior. However, public officials and other individuals are sometimes barred from accepting payment for anything related to their position, so money cannot be used in experiments (e.g., Butler and Kousser 2015). We assess whether donations to charity can be used to incentivize public officials, as an alternative to traditional monetary inducements.

This paper discusses how audit studies can be adapted to test the effectiveness of interventions aimed at reducing discrimination. We conducted an adapted audit experiment to test whether making officials aware of bias could reduce levels of racial bias. While the limitations of our design make it difficult to assess where information alone can reduce bias, our study makes two important contributions. First, we replicate prior studies by showing that white, local elected officials are less responsive to black constituents. That local officials exhibit biased behavior is particularly worrisome, as local government is often the level that most directly affects citizens’ daily lives. Second, we provide several suggestions for future audit studies that draw from the strengths and weaknesses of our own design. We hope that they will help improve future work on identifying and reducing discrimination.

In 1995, Beck and Katz (B&K) instructed the profession on “What to do (and not to do) with time-series, cross-section data,” and almost instantly their prescriptions became the new orthodoxy for practitioners. Our assessment of the intellectual aftermath of this paper, however, does not inspire confidence in the conclusions reached during the past decade. The 195 papers we reviewed show a widespread failure to diagnose and treat common problems of time-series, cross-section (TSCS) data analysis. To show the importance of the consequences of the B&K assumptions, we replicate eight papers in prominent journals and find that simple alternative specifications often lead to drastically different conclusions. Finally, we summarize many of the statistical issues relative to TSCS data and show that there is a lot more to do with TSCS data than many researchers have apparently assumed.

We provide an introduction to the regression discontinuity design (RDD) and use the technique to evaluate models of sequential Senate elections predicting that the winning party for one Senate seat will receive fewer votes in the next election for the other seat. Using data on U.S. Senate elections from 1946 to 2004, we find strong evidence that the outcomes of the elections for the two Senate seats are independent.

Researchers studying discrimination and bias frequently conduct experiments that use racially distinctive names to signal race. The ability of these experiments to speak to racial discrimination depends on the excludability assumption that subjects’ responses to these names are driven by their reaction to the individual’s putative race and not some other factor. We use results from an audit study with a large number of aliases and data from detailed public records to empirically test the excludability assumption undergirding the use of racially distinctive names. The detailed public records allow us to measure the signals about socioeconomic status and political resources that each name used in the study possibly could send. We then reanalyze the audit study to see whether these signals predict legislators’ likelihood of responding. We find no evidence that politicians respond to this other information, thus providing empirical support for the excludability assumption.

A plausible mechanism underlying flavonoid-associated cognitive effects is increased cerebral blood flow (CBF). However, behavioural and CBF effects following flavanone-rich juice consumption have not been explored. The aim of this study was to investigate whether consumption of flavanone-rich juice is associated with acute cognitive benefits and increased regional CBF in healthy, young adults. An acute, single-blind, randomised, cross-over design was applied with two 500-ml drink conditions – high-flavanone (HF; 70·5 mg) drink and an energy-, and vitamin C- matched, zero-flavanone control. A total of twenty-four healthy young adults aged 18–30 years underwent cognitive testing at baseline and 2-h after drink consumption. A further sixteen, healthy, young adults were recruited for functional MRI assessment, whereby CBF was measured with arterial spin labelling during conscious resting state at baseline as well as 2 and 5 h after drink consumption. The HF drink was associated with significantly increased regional perfusion in the inferior and middle right frontal gyrus at 2 h relative to baseline and the control drink. In addition, the HF drink was associated with significantly improved performance on the Digit Symbol Substitution Test at 2 h relative to baseline and the control drink, but no effects were observed on any other behavioural cognitive tests. These results demonstrate that consumption of flavanone-rich citrus juice in quantities commonly consumed can acutely enhance blood flow to the brain in healthy, young adults. However, further studies are required to establish a direct causal link between increased CBF and enhanced behavioural outcomes following citrus juice ingestion.

This article considers the hypothesis that the positive actions taken by members of Congress (MCs) influence citizens’ evaluations of them, their party, and Congress as an institution. We begin with a look at the available cross-sectional survey data on contact with legislators and legislator and institutional approval. Their legislative responsiveness appears to have a small spillover effect on institutions. However, when we employ a unique panel design that controls for prior levels of opinion and avoids recall bias, we find no evidence of spillover effects. Overall, we find that constituents who received a response from their own MC evaluate that representative more positively than those who did not receive a response, but legislator responsiveness does not predict evaluations of the MC’s political party or the Congress.

A large literature argues that the committee assignment process plays an important role in shaping legislative politics because some committees provide legislators with substantial benefits. However, evaluating the degree to which legislators benefit from winning their preferred assignments has been challenging with existing data. This paper sheds light on the benefits legislators accrue from winning their preferred committee assignments by exploiting rules in Arkansas’ state legislature, where legislators select their own committee assignments in a randomized order. The natural experiment indicates that legislators reap at most limited rewards from winning their preferred assignments. These results potentially raise questions about the robustness of widely held assumptions in literatures on party discipline and legislative organization.

Since the mid-19th century, western Oregon's Willamette Valley has been a source of remains from a wide variety of extinct megafauna. Few of these have been previously described or dated, but new chronologic and isotopic analyses in conjunction with updated evaluations of stratigraphic context provide substantial new information on the species present, timing of losses, and paleoenvironmental conditions. Using subfossil material from the northern valley, we use AMS radiocarbon dating, stable isotope (δ13C and δ15N) analyses, and taxonomic dietary specialization and habitat preferences to reconstruct environments and to develop a local chronology of events that we then compare with continental and regional archaeological and paleoenvironmental data. Analysis of twelve bone specimens demonstrates the presence of bison, mammoth, horse, sloth, and mastodon from ~ 15,000–13,000 cal yr BP. The latest ages coincide with changing regional climate corresponding to the onset of the Younger Dryas. It is suggested that cooling conditions led to increased forest cover, and along with river aggradation, reduced the area of preferred habitat for the larger bodied herbivores, which contributed to the demise of local megafauna. Archaeological evidence for megafauna–human interactions in the Pacific Northwest is scarce, limiting our ability to address the human role in causing extinction.