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901.
Léopold Simar 《Econometric Reviews》2013,32(1):62-98
Conventional approaches for inference about efficiency in parametric stochastic frontier (PSF) models are based on percentiles of the estimated distribution of the one-sided error term, conditional on the composite error. When used as prediction intervals, coverage is poor when the signal-to-noise ratio is low, but improves slowly as sample size increases. We show that prediction intervals estimated by bagging yield much better coverages than the conventional approach, even with low signal-to-noise ratios. We also present a bootstrap method that gives confidence interval estimates for (conditional) expectations of efficiency, and which have good coverage properties that improve with sample size. In addition, researchers who estimate PSF models typically reject models, samples, or both when residuals have skewness in the “wrong” direction, i.e., in a direction that would seem to indicate absence of inefficiency. We show that correctly specified models can generate samples with “wrongly” skewed residuals, even when the variance of the inefficiency process is nonzero. Both our bagging and bootstrap methods provide useful information about inefficiency and model parameters irrespective of whether residuals have skewness in the desired direction. 相似文献
902.
Aurélien Baillon Han Bleichrodt Zhenxing Huang Rogier Potter van Loon 《Journal of Risk and Uncertainty》2017,54(3):269-281
Empirical studies of ambiguity aversion often use measures that are not grounded in theory. This paper shows how a theoretically-founded measure of ambiguity aversion can be derived from Hansen and Sargent’s theory of multiplier preferences. Multiplier preferences are used in macroeconomics to capture model uncertainty. At the micro level, they have not been applied yet, because they do not permit ambiguity seeking, which is usually observed for a substantial proportion of subjects. We give a preference foundation for (extended) multiplier preferences accommodating both ambiguity aversion and ambiguity seeking and we propose a simple method to measure them using matching probabilities. We illustrate our method in two large representative samples (Dutch and American) and obtain the first micro estimates of multiplier preferences. 相似文献
903.
Each year, thousands of children who cross international borders are destined for homes with adoptive families. For most, this journey from their homeland brings them to loving new homes where they will thrive and prosper. For others, the journey is hazardous and the destination uncertain. 相似文献
904.
Abstract A two-phase study was conducted on the relationship between organizational climate variables and burnout among personnel in a multifunction community service agency. Initial interviews with a small pilot sample identified major sources of stress, which were then incorporated into a second-phase questionnaire to all staff. Multiple regression analyses illustrated that perceived interactions between head office administrators and sections of the agency contributed significantly to emotional exhaustion, whereas perceptions of within-section interactions and involvement in decision-making had a positive impact on personal accomplishment. Perceived communication levels, however, were negatively related to personal accomplishment. The findings suggest the importance of organizational variables and highlight strategies for burnout reduction and effective stress management in human service organizations. 相似文献
905.
James R. Hillard M.D. Cherie L. Kitchell L.C.S.W. U. G. Turner III M.D. Richard P. Keeling M.D. Rebecca F. Shank M.Ed. 《Journal of American college health : J of ACH》2013,61(3):112-117
Abstract Genital herpes virus infection is an important target for health education efforts because of its apparently rising incidence in the college student population and because it can have potentially serious psychological as well as medical consequences. In order to better understand the health education and counseling needs of students, the present study surveyed knowledge and attitudes about genital herpes of 190 university students using a gynecology clinic and of 161 students using a general medical clinic. The students were found to have a high degree of familiarity with the disease, its cause, and mode of transmission, but tended to view the consequences of the disease as more severe than is actually warranted by the common medical complications. There was some degree of misinformation about prevention and treatment of the disease and some negative attitudes about patients suffering from it, but the survey respondents endorsed a high level of responsible behavior with regard to the disease and expressed some optimism about the possibility of adapting to it. These findings suggest specific misconceptions about genital herpes that might be amenable to a mass education approach. They also suggest the need for a counseling program that centers around reasonable reassurance and appropriately positive psychological and medical management for newly diagnosed patients. 相似文献
906.
This study investigates how ritual practices are disrupted in disasters and the ways people deal with those situations. We employ structural ritualization theory to conduct this investigation focusing on deritualization, which refers to the breakdown or loss of ritualized activities that occur in daily life. The thesis of this paper is that ritual practices are disrupted in a disaster leading to the breakdown of action and meaning. Data were collected from 19 seminal sociological studies from the National Academy of Sciences published first under the name of the Committee on Disaster Studies (1951–1957) and then under the rubric of the Disaster Research Group (1957–1962). A content analysis of these studies revealed many instances of deritualization. Deritualization is manifested or most evident through its effects on action and meaning in rituals. Examples were categorized according to the loss of action, meaning, or a combination of both. 相似文献
907.
908.
909.
This paper makes the point that although U.K. agriculture has become more efficient in many ways, it has become less efficient in its use of energy. Moreover, although farming utilises less than 3 per cent of national power energy consumption and produces over 40 per cent of the nation's food, there are no predominant users of energy in the U.K. Thus small savings in each individual industry, including agriculture, must be effected. How this can be achieved is discussed. But the paper concludes that it may well take another ‘energy crisis’ before farmers and growers respond by modifying their production systems accordingly. 相似文献
910.