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Collision-energy dependence of second-order off-diagonal and diagonal cumulants of net-charge, net-proton, and net-kaon multiplicity distributions in Au + Au collisions
No full textWe report the first measurements of a complete second-order cumulant matrix of net-charge, net-proton and net-kaon multiplicity distributions for the first phase of the beam energy scan program at RHIC. This includes the centrality and, for the first time, the pseudorapidity window dependence of both diagonal and off-diagonal cumulants in Au+Au collisions at = 7.7-200 GeV. Within the available acceptance of , the cumulants grow linearly with the pseudorapidity window. Relative to the corresponding measurements in peripheral collisions, the ratio of off-diagonal over diagonal cumulants in central collisions indicates an excess correlation between net-charge and net-kaon, as well as between net-charge and net-proton. The strength of such excess correlation increases with the collision energy. The correlation between net-proton and net-kaon multiplicity distributions is observed to be negative at = 200 GeV and change to positive at the lowest collision energy. Model calculations based on non-thermal (UrQMD) and thermal (HRG) production of hadrons cannot explain the data. These measurements will help map the QCD phase diagram, constrain hadron resonance gas model calculations and provide new insights on the energy dependence of baryon-strangeness correlations
Spatiotemporal Variability of Tropical Cyclone Precipitation Using a High-Resolution, Gridded (0.25° × 0.25°) Dataset for the Eastern United States, 1948-2015
Get PDFTropical cyclones (TCs) are an important source of precipitation for much of the eastern United States. However, our understanding of the spatiotemporal variability of tropical cyclone precipitation (TCP) and the connections to large-scale atmospheric circulation is limited by irregularly distributed rain gauges and short records of satellite measurements. To address this, we developed a new gridded (0.25° × 0.25°) publicly available dataset of TCP (1948–2015; Tropical Cyclone Precipitation Dataset, or TCPDat) using TC tracks to identify TCP within an existing gridded precipitation dataset. TCPDat was used to characterize total June–November TCP and percentage contribution to total June–November precipitation. TCP totals and contributions had maxima on the Louisiana, North Carolina, and Texas coasts, substantially decreasing farther inland at rates of approximately 6.2–6.7 mm km. Few statistically significant trends were discovered in either TCP totals or percentage contribution. TCP is positively related to an index of the position and strength of the western flank of the North Atlantic subtropical high (NASH), with the strongest correlations concentrated in the southeastern United States. Weaker inverse correlations between TCP and El Niño–Southern Oscillation are seen throughout the study site. Ultimately, spatial variations of TCP are more closely linked to variations in the NASH flank position or strength than to the ENSO index. The TCP dataset developed in this study is an important step in understanding hurricane–climate interactions and the impacts of TCs on communities, water resources, and ecosystems in the eastern United States
The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. XVIII. Proper-motion Kinematics of Multiple Stellar Populations in the Core Regions of NGC 6352
Get PDFWe present the analysis of the radial distributions and kinematic properties of the multiple stellar populations (mPOPs) hosted in the globular cluster (GC) NGC 6352 as part of the Hubble Space Telescope "UV Legacy Survey of Galactic Globular Clusters" program. NGC 6352 is one of the few GCs for which the mPOP tagging in appropriate color–magnitude diagrams is clear in all evolutionary sequences. We computed high-precision stellar proper motions for the stars from the cluster's core out to 75 arcsec (~1.5 core radii, or ~0.6 half-light radii). We find that, in the region explored, first- and second-generation stars share the same radial distribution and kinematic properties. Velocity dispersions, anisotropy radial profiles, differential rotation, and level of energy equipartition, all suggest that NGC 6352 is probably in an advanced evolutionary stage, and any possible difference in the structural and kinematic properties of its mPOPs have been erased by dynamical processes in the core of the cluster. We also provide an estimate of the mass of blue stragglers and of main-sequence binaries through kinematics alone. In general, in order to build a complete dynamical picture of this and other GCs, it will be essential to extend the analyses presented in this paper to the GCs' outer regions where some memories of the initial differences in the mPOP properties, and those imprinted by dynamical processes, might still be present
Students' Understanding of Institutional Practices: The Missing Dimension in Human Rights Education
Get PDFThis study used task-based group interviews with young adolescents in four countries to investigate their understanding of the causes of human rights violations, means for protecting human rights, and their own potential role in ensuring human rights. Although students recognized the role of personal and institutional factors in both violating and protecting human rights, their ideas for influencing human rights focused primarily on the personal contexts with which they were most familiar. Their understanding of political and economic mechanisms was much less elaborate. These findings suggest the need for curricula that equip students with the complex and specialized knowledge that would enable them to engage in a range of meaningful civic action, both in their lives now and as adults
Optimal trade policy with trade imbalances
No full textOptimal trade and capital control policies are characterized under a dynamic model with endogenous trade imbalances. In the absence of capital controls, optimal trade protection is counter-cyclical. Optimal use of capital controls, however, dampens the time-variation of optimal trade taxes. Generally, trade imbalances are not predictive of optimal policy. However, optimal trade policy and equilibrium trade imbalances move together when a country grows consistently faster or slower than the rest of the world. Quantifying the model for the U.S. economy shows that welfare gains from optimal policy are largely due to static terms-of-trade effects, implying that gains from time-varying tariffs or capital controls are small
Dropout rates of in‐person psychosocial substance use disorder treatments: a systematic review and meta‐analysis
No full textBackground and Aims: Relapse rates for psychosocial substance use disorder (SUD) treatments are high, and dropout is a robust predictor of relapse. No meta-analyses have assessed dropout rates in studies of psychosocial SUD treatment. The objective of this meta-analysis, therefore, was to estimate average dropout rates of in-person psychosocial SUD treatment and evaluate potential moderators of this outcome. Design: A comprehensive meta-analysis of dropout rates of studies of in-person psychosocial SUD treatment. Studies included RCTs and cohort studies. Participants/Cases: 151 studies, 338 study arms, and 299 dropout rates including 26,243 participants. Measurements: Databases were searched for studies of SUD treatment that included an in-person-facilitated psychosocial component. Meta-analyses and meta-regressions were conducted to estimate dropout rates and identify moderators of dropout, including 22 participant characteristics, two facilitator characteristics, and 15 treatment characteristics. Pooled estimates were calculated with random-effects analyses accounting for the hierarchical structure of study arms nested within studies. Findings: The average dropout rate across all studies and study arms was 30.42%(95% CI[27.22,33.83], 95% PI[6.25,74.15]) with substantial heterogeneity (I2=93.7%, p<0.0001). Studies including a higher percentage of African Americans and lower-income individuals were associated with higher dropout rates. At intake, a greater percentage of heroin use days and cigarettes/day were associated with lower dropout rates, whereas heavier cocaine use was associated with higher dropout rates. Programs characterized by more treatment sessions and greater average session length were associated with higher dropout rates. Dropout rates were highest for studies targeting cocaine, methamphetamines, and major stimulants (broadly defined), and lowest for studies targeting alcohol, tobacco, and heroin, though there were few studies on methamphetamines, major stimulants, and heroin. Facilitator characteristics were not associated with dropout. Conclusions: Approximately 3 of 10 participants drop out of in-person psychosocial SUD treatment studies. There was wide variability in reported dropout rates, and several moderators of this outcome were identified. Additional research is needed to test interactions of moderators to potentially decrease dropout
Management and Effects of In-Store Promotional Displays
Get PDFProblem denition: We examine a brick-and-mortar retailer's choice of which product to include in a promotional display (e.g., an \endcap" display). The display provides a visibility advantage to both the featured product and its category, but it also has consequences for customer trac and substitution. Academic / practical relevance: While there has been considerable academic interest in the assortment planning problem (which products to oer?) and in the shelf-space allocation problem (how much space to devote to each product?), little attention has been paid to the problem of where to place products in the store. Promotional display choice can serve as a powerful demand-shaping lever for retailers. A good understanding of this problem can also facilitate a retailer's negotiations with manufacturers. Methodology: We develop analytical insights using a problem formulation based on a nested multinomial logit (NMNL) model of customer choice. Results: When choosing a promotional product from a xed category, the only possible optimal choices for promotional display lie along an effecient set" drawn in terms of product popularities and margins. The optimal choice along the frontier depends on a quantity we call "aisle attractiveness" that depends on several category-level parameters. The value of the display to a category pivots on whether the display's role is primarily to expand demand for the category or to shape substitution within the category. Managerial implications: Our work provides guidance for how retailers can use and value promotional displays eectively. We highlight the importance of considering externalities of a display decision on store trac and demand for other products
Artistic Control and Partnership: Jewish Studies Programs and the Incubation of New Musical Works
Get PDFOn May 14, 2018, I took my seat in the Robert Moss Theater, a small, well equipped performance space in Greenwich Village across from the New York Public Theater, to watch a performance of Or Matias’s new musical The Wave. Sitting among actors, creatives, and friends and family of the cast, I witnessed a dozen Indiana University musical theater students present the latest version of the powerful work, directed by Chloe Treat. To the undergraduate cast and musicians, the performance culminated a dream workshop year. They developed the work with the artists in two three-week stints at Indiana University before being flown into the epicenter of the musical theater world to help the artists transition the work to the next level. Their New York experience was rigorous, involving three days of twelve-hour rehearsals and the regular incorporation of new changes (including a new opening). In the end, however, their dedicated and nuanced performances showed a year’s growth with their characters, as they dramatized with naturalness and depth the story of a Palo Alto teacher’s social experiment with his class. I had seen and been moved by the show in the six previous performances at Indiana University, but watching the students enact their roles on a professional stage offered a poignant example of how successful artistic collaborations can mutually elevate a work, its creators, and its participants
Appealing to Sense and Sensibility: System 1 and System 2 Interventions for Fake News on Social Media
Get PDFDisinformation on social media—commonly called “fake news”—has become a major concern around the world, and many fact-checking initiatives have been launched to mitigate the problem. The way fact-checking results are presented to social media users is important because if the presentation format is not persuasive, fact checking may not be effective. For instance, Facebook tested the idea of flagging dubious articles in 2017 but concluded that it was ineffective and subsequently removed the feature. We conducted three experiments with social media users to investigate two different approaches to implementing a fake news flag, one designed to have its primary effect when processed by automatic cognition (System 1) and the other designed to have its primary effect when processed by deliberate cognition (System 2). We found that both interventions were effective, and an intervention that combined both approaches was about twice as effective. We also found that awareness training on the meaning of the flags increased the effectiveness of the System 2 intervention, but not the System 1 intervention, exactly as theory predicts. Believability, in turn, influenced the extent to which users would engage with the article (e.g., read, like, comment, and share). Our results suggest that both theoretical routes can be used—separately or together—in the presentation of fact-checking results in order to reduce the influence of fake news on the users
Digital Nudging: Numeric and Semantic Priming in E-Commerce
No full textMost research on e-commerce has focused on deliberate rational cognition, yet research in psychology and marketing suggests that buying decisions may also be influenced by priming (a form of what Information Systems researchers have called digital nudging). We conducted seven experiments to investigate the impact of two types of priming (numeric priming and semantic priming) delivered through what appeared to be advertisements on an e-commerce website. We found that numeric priming had a small but significant effect on consumers’ willingness to pay when the value of the product was unclear, but had no effect when products displayed a manufacturer’s suggested retail price (MSRP) or a fixed selling price. Semantic priming had larger effects on willingness to pay and the effects were significant but smaller in the presence of an MSRP. Thus the combination of numeric and semantic priming has a larger impact on consumers’ willingness to pay. Taken together, these experiments show that some of the research on numeric priming and semantic priming done in offline settings generalizes to e-commerce settings, but there are important boundary conditions to their effects in e-commerce that have not been noted in offline settings. In online auctions (e.g., eBay), sellers can influence customers to pay more for products whose value is unclear by displaying products with clearly labelled high prices alongside the products the consumer searched for. However, such tactics will have only small effects for auctions of products whose price is known (e.g., those with an MSRP) and no effects on products with clearly listed prices (e.g., Amazon)