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931.
Uniformly most powerful Bayesian tests (UMPBTs) are a new class of Bayesian tests in which null hypotheses are rejected if their Bayes factor exceeds a specified threshold. The alternative hypotheses in UMPBTs are defined to maximize the probability that the null hypothesis is rejected. Here, we generalize the notion of UMPBTs by restricting the class of alternative hypotheses over which this maximization is performed, resulting in restricted most powerful Bayesian tests (RMPBTs). We then derive RMPBTs for linear models by restricting alternative hypotheses to g priors. For linear models, the rejection regions of RMPBTs coincide with those of usual frequentist F‐tests, provided that the evidence thresholds for the RMPBTs are appropriately matched to the size of the classical tests. This correspondence supplies default Bayes factors for many common tests of linear hypotheses. We illustrate the use of RMPBTs for ANOVA tests and t‐tests and compare their performance in numerical studies. 相似文献
932.
This study focuses on differences in sense of belonging between lesbian, gay, and bisexual (LGB) and heterosexual students. Data from 1,745 secondary school students were collected with an online survey. Step-wise multiple regression analyses was used to investigate the relationship between sexual orientation and sense of school belonging. The results show that sexual orientation has an impact on sense of belonging for girls, but not for boys. Perceived discrimination and LGB friendliness of the school appeared to be important indicators of sense of belonging for all the respondents, irrespective of their sexual orientation. 相似文献
933.
While piece rates are routinely associated with higher productivity and wages, they can also generate unanticipated effects.
Using cross-country European data, we provide among the first general survey evidence of a strong link between piece rates
and workplace injury. Despite controls for workplace hazards, job characteristics and worker effort, piece rates workers suffer
a 5 percentage point greater likelihood of injury. This remains despite attempts to control for endogeneity and heterogeneity.
As piece rate wage premium estimates rarely control for injury likelihood, this raises the specter that part of that premium
reflects a compensating wage differential for risk of injury. 相似文献
934.
This research uses a two-stage maximal covering location problem (MCLP) model to develop Inter continental ballistic missile (ICBM) maintenance schedules for the US Air Force. Solutions are compared to actual missile maintenance activities accomplished at F. E. Warren Air Force Base (AFB), Wyoming in May 2005. Sensitivity analysis is performed to determine the impact of altering security response times and the number of security patrol areas on the quality of daily maintenance schedules and personnel usage. Results indicate marked improvement over traditional Air Force scheduling methods. In addition sensitivity analysis identifies the levels at which the quality and quantity of maintenance performance is impacted. 相似文献
935.
Gordon H. Copp Lorenzo Vilizzi John Mumford Gemma V. Fenwick Michael J. Godard Rodolphe E. Gozlan 《Risk analysis》2009,29(3):457-467
Adapted from the weed risk assessment (WRA) of Pheloung, Williams, and Halloy, the fish invasiveness scoring kit (FISK) was proposed as a screening tool for freshwater fishes. This article describes improvements to FISK, in particular the incorporation of confidence (certainty/uncertainty) ranking of the assessors' responses, and reports on the calibration of the score system, specifically: determination of most appropriate score thresholds for classifying nonnative species into low-, medium-, and high-risk categories, assessment of the patterns of assessors' confidences in their responses in the FISK assessments. Using receiver operating characteristic (ROC) curves, FISK was demonstrated to distinguish accurately (and with statistical confidence) between potentially invasive and noninvasive species of nonnative fishes, with the statistically appropriate threshold score for high-risk species scores being ≥19. Within the group of species classed as high risk using this new threshold, a "higher risk" category could be visually identified, at present consisting of two species (topmouth gudgeon Pseudorasbora parva and gibel carp Carassius gibelio ). FISK represents a useful and viable tool to aid decision- and policymakers in assessing and classifying freshwater fishes according to their potential invasiveness. 相似文献
936.
This paper develops a tractable econometric model of optimal migration, focusing on expected income as the main economic influence on migration. The model improves on previous work in two respects: it covers optimal sequences of location decisions (rather than a single once‐for‐all choice) and it allows for many alternative location choices. The model is estimated using panel data from the National Longitudinal Survey of Youth on white males with a high‐school education. Our main conclusion is that interstate migration decisions are influenced to a substantial extent by income prospects. The results suggest that the link between income and migration decisions is driven both by geographic differences in mean wages and by a tendency to move in search of a better locational match when the income realization in the current location is unfavorable. 相似文献
937.
938.
John Martin Perry 《国际人才交流》2012,(9):61-61
It was with some trepidation that I first went to teach in China, in 2004.All my information about China had come from old newsreel films. Basically,I was expecting a drab, black and white place where people queued to use the local telephone. 相似文献
939.
Objectives. Within the long line of inquiry on demand for sport, one area that has gone relatively unexamined is that of domestic migration. In this research, the relationship between population migration and team loyalty is explored. Methods. A linear mixed model uses data from the U.S. Census Bureau and Nielsen Company to analyze the effect domestic migration has on demand for National Football League games. Results. Ratings were higher in population centers with smaller per‐capita population inflow (regardless of the origins of the inflow). The results further showed that increases in population flow from City A to City B were associated with increased demand for broadcasts in City B when Team B visited City A. Conclusions. The first finding suggests that sports viewership is not utilized as a vehicle for domestic transplants to integrate into their new community. The second finding suggests there is a nostalgia effect for an individual's previous hometown, though not necessarily for the team representing it in the league. 相似文献
940.
Nigeria's oil guarantees its role in the global economy; however, the state's overwhelming weaknesses perpetuate a high level of volatility vis-à-vis the potential for an immediate disruption of the national, regional, and global environment. This study presents a current qualitative analysis of Nigeria to produce a model that characterizes current conditions in the state and the state response to the nefarious acts in the delta region. This model will serve as a baseline for a significant iteration of the model that reflects the delta region counter-insurgency at various levels of strength: a what-if scenario of the region with an increase of state security over southern separatists, insurgents seeking to gain control of the oil assets. The conjectured model serves to inform/educate decision and policy makers in developing proactive, effective strategies to counter existent and potential threats in the Niger Delta. 相似文献