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991.
John Charles Bradbury 《Economic inquiry》2019,57(1):121-140
This study investigates determinants of revenue in North America's four major professional sports leagues. Revenue is positively associated with on‐field success in baseball (MLB), basketball (NBA), and hockey (NHL), but not in football (NFL). The returns to success are not diminishing as commonly assumed, which casts doubt on the uncertainty of outcome hypothesis, and differences across leagues are consistent with revenue sharing arrangements. Estimates indicate a strong negative but diminishing relationship between stadium age and revenue. Teams in larger markets generate more revenue than smaller markets, but the returns to success do not differ according to market size. (JEL Z21) 相似文献
992.
AbstractA convention in designing randomized clinical trials has been to choose sample sizes that yield specified statistical power when testing hypotheses about treatment response. Manski and Tetenov recently critiqued this convention and proposed enrollment of sufficiently many subjects to enable near-optimal treatment choices. This article develops a refined version of that analysis applicable to trials comparing aggressive treatment of patients with surveillance. The need for a refined analysis arises because the earlier work assumed that there is only a primary health outcome of interest, without secondary outcomes. An important aspect of choice between surveillance and aggressive treatment is that the latter may have side effects. One should then consider how the primary outcome and side effects jointly determine patient welfare. This requires new analysis of sample design. As a case study, we reconsider a trial comparing nodal observation and lymph node dissection when treating patients with cutaneous melanoma. Using a statistical power calculation, the investigators assigned 971 patients to dissection and 968 to observation. We conclude that assigning 244 patients to each option would yield findings that enable suitably near-optimal treatment choice. Thus, a much smaller sample size would have sufficed to inform clinical practice. 相似文献
993.
Xavier Noël Mélanie Saeremans Charles Kornreich Antoine Bechara Nematollah Jaafari Carole Fantini-Hauwel 《Journal of gambling studies / co-sponsored by the National Council on Problem Gambling and Institute for the Study of Gambling and Commercial Gaming》2018,34(4):1049-1066
A great number of individuals with persistent problematic gambling behavior exhibit alexithymic tendencies, greater impulsivity, impaired working memory and poor mood. However, the relationship between these cognitive, affective and personality factors in problem gambling remains poorly understood. Our aim was to investigate multiple pathways of the alexithymia and problem gambling relationship. One hundred and six male subjects with different levels of gambling problem severity were recruited. Alexithymia, impulsivity and verbal working memory were evaluated, and their relationships to disordered gambling was examined by means of a path analysis. Results indicate that alexithymia is related to an increase in the severity of gambling indirectly, i.e., through distress severity. In addition, a rise of alexithymic tendencies was also associated with problem gambling severity through enhanced impulsivity that directly increased distress. Working memory capacity failed to significantly impact our path model. Overall, our findings contribute a new finding to the literature by highlighting the importance of alexithymia, in addition to impulsivity, in the understanding of gambling problem severity and its clinical course. 相似文献
994.
The Impact of Blamer‐softening on Romantic Attachment in Emotionally Focused Couples Therapy 下载免费PDF全文
Melissa Burgess Moser Susan M. Johnson Tracy L. Dalgleish Stephanie A. Wiebe Giorgio A. Tasca 《Journal of marital and family therapy》2018,44(4):640-654
Emotionally Focused Couples Therapy (EFT; Johnson, 2004 ) treats relationship distress by targeting couples' relationship‐specific attachment insecurity. In this study, we used hierarchical linear modeling (Singer & Willett, 2003 ) to examine intercept and slope discontinuities in softened couples' trajectories of change in relationship satisfaction and relationship‐specific attachment over the course of therapy from a total sample of 32 couples. Softened couples (n = 16) reported a significant increase in relationship satisfaction and a significant decrease in attachment avoidance at the softening session. Although softened couples displayed an initial increase in relationship‐specific attachment anxiety at the softening session, their scores significantly decreased across post‐softening sessions. Results demonstrated the importance of the blamer‐softening change event in facilitating change in EFT. 相似文献
995.
Falynn C. Turley David Redden Janice L. Case Charles Katholi Jeff Szychowski Derek DuBay 《Journal of Statistical Computation and Simulation》2018,88(4):769-784
Propensity score analysis (PSA) is a technique to correct for potential confounding in observational studies. Covariate adjustment, matching, stratification, and inverse weighting are the four most commonly used methods involving propensity scores. The main goal of this research is to determine which PSA method performs the best in terms of protecting against spurious association detection, as measured by Type I error rate, while maintaining sufficient power to detect a true association, if one exists. An examination of these PSA methods along with ordinary least squares regression was conducted under two cases: correct PSA model specification and incorrect PSA model specification. PSA covariate adjustment and PSA matching maintain the nominal Type I error rate, when the PSA model is correctly specified, but only PSA covariate adjustment achieves adequate power levels. Other methods produced conservative Type I Errors in some scenarios, while liberal Type I error rates were observed in other scenarios. 相似文献
996.
997.
Inaccurate perceptions of audience can cause public relations practitioners to overreact or underreact to a situation, which brings about unintended consequences. We draw on the third-person effect research to identify examples and outline the conditions when the overestimation or underestimation of media effects can motivate key players to engage in restrictive, corrective, promotional, and resistance behaviors. Then, we recommend approaches that can help public relations practitioners better reflect and manage corporate communication. In short, the approaches involve: (a) determining the nature of the presumed effect from the audience perspective and going beyond the categorical positive/negative message, (b) assessing the level of the presumed effect and considering also the possibility of the first- as well as the second-person effect, and (c) assessing the influence of the perceived effect on behaviors that have the potential to directly as well as indirectly affect the company. 相似文献
998.
Charles C. Taylor Kanti V. Mardia Marco Di Marzio Agnese Panzera 《Journal of applied statistics》2012,39(11):2379-2388
Measuring the quality of determined protein structures is a very important problem in bioinformatics. Kernel density estimation is a well-known nonparametric method which is often used for exploratory data analysis. Recent advances, which have extended previous linear methods to multi-dimensional circular data, give a sound basis for the analysis of conformational angles of protein backbones, which lie on the torus. By using an energy test, which is based on interpoint distances, we initially investigate the dependence of the angles on the amino acid type. Then, by computing tail probabilities which are based on amino-acid conditional density estimates, a method is proposed which permits inference on a test set of data. This can be used, for example, to validate protein structures, choose between possible protein predictions and highlight unusual residue angles. 相似文献
999.
1000.
Charles L. Baum 《Journal of population economics》2012,25(4):1307-1340
With over 66% of Americans overweight, expectant mothers are unusual because they are encouraged to gain weight while pregnant. Food stamp receipt (FSR) may facilitate recommended weight gain by providing resources for food and nutrition. I examine the effects of FSR on the amount of weight gained by low-income expectant mothers using NLSY79 data. Results indicate FSR decreases the probability gaining insufficient weight but does not exacerbate the probability of gaining too much weight. Examining the effects of FSR on pregnancy weight gain is important because low birth weight is more likely when expectant mothers gain insufficient weight. 相似文献