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1.
Stephen J. Ruberg Frank E. Harrell Jr. Margaret Gamalo-Siebers Lisa LaVange J. Jack Lee Karen Price 《The American statistician》2019,73(1):319-327
ABSTRACTThe cost and time of pharmaceutical drug development continue to grow at rates that many say are unsustainable. These trends have enormous impact on what treatments get to patients, when they get them and how they are used. The statistical framework for supporting decisions in regulated clinical development of new medicines has followed a traditional path of frequentist methodology. Trials using hypothesis tests of “no treatment effect” are done routinely, and the p-value < 0.05 is often the determinant of what constitutes a “successful” trial. Many drugs fail in clinical development, adding to the cost of new medicines, and some evidence points blame at the deficiencies of the frequentist paradigm. An unknown number effective medicines may have been abandoned because trials were declared “unsuccessful” due to a p-value exceeding 0.05. Recently, the Bayesian paradigm has shown utility in the clinical drug development process for its probability-based inference. We argue for a Bayesian approach that employs data from other trials as a “prior” for Phase 3 trials so that synthesized evidence across trials can be utilized to compute probability statements that are valuable for understanding the magnitude of treatment effect. Such a Bayesian paradigm provides a promising framework for improving statistical inference and regulatory decision making. 相似文献
2.
Existence and Nash implementation of efficient sharing rules for a commonly owned technology 总被引:2,自引:0,他引:2
Suppose that a group of individuals owns collectively a technology which produces a consumption good by means of a (possibly
heterogeneous) input. A sharing rule associates input contributions with a vector of consumptions that are technologically
feasible. We show that the set of allocations obtained by any continuous sharing rule contains Pareto efficient allocations.
We also present a mechanism that implements in Nash equilibrium the Pareto efficient allocations contained in an arbitrary
sharing rule.
Received: 29 June 1998/Accepted: 15 November 2000 相似文献
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Tracy AJ Erkut S 《Sociological perspectives : SP : official publication of the Pacific Sociological Association》2002,45(4):445-466
Athletics is the most prominent extracurricular activity in U.S. secondary schools in terms of student participation and school budgets. The latter is often justified on the grounds that healthy bodies produce healthy minds, that school sports boost school spirit, and that participation in school-based sports increases students' self-esteem. In this article we examine the interrelationships among participation in a school-based sport and the benefits assumed to be associated with it. Specifically, we test a model that postulates that school spirit, operationalized as attachment to school, and healthy bodies, operationalized as a sense of physical well-being, mediate the relationship between school sports and self-esteem. Data from the National Longitudinal Study of Adolescent Health on Caucasian and African American girls and boys were employed to test the model. School attachment and physical well-being absorbed the statistical effect of participating in a sport for all four gender-by-race groups. Among Caucasian girls a negative residual effect of sports participation was observed, which suggests that sports participation encapsulates multiple effects with contradictory influences. For African American girls school attachment by itself was not a significant mediator of the effect of sports participation on self-esteem. For all groups a sense of physical well-being was the more powerful mediator. 相似文献
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The authors examined the impact of sense of coherence on the career thought processes of a sample of college students. A. Antonovsky (1987) defined sense of coherence as the global orientation that the world is comprehensible, manageable, and meaningful. Study participants completed the Sense of Coherence Scale (A. Antonovsky, 1987) and the Career Thoughts Inventory (CTI; J. P. Sampson, G. W. Peterson, J. G. Lenz, R. C. Reardon, & D. E. Saunders, 1996). Multivariate tests indicated a medium relationship between sense of coherence and CTI Total and subscale scores; sense of coherence accounted for 14% of the variance. Univariate tests also indicated a medium relationship between sense of coherence and each subscale. 相似文献
7.
Colin C. Williams 《The Sociological review》2002,50(4):525-542
A recurring theme across the social sciences is that non‐capitalist production is disappearing albeit slowly and unevenly, and is being replaced by a commodified economy in which goods and services are produced by capitalist firms for a profit under conditions of market exchange. In this paper, however, I evaluate critically this commodification thesis. Even in the heartland of commoditisation ‐ the advanced economies. Large economic spaces are identified where alternative economic relations and motives prevail. Rather than view them as leftovers of pre‐capitalist formations, this paper argues that they are the result of both the contradictions inherent in the structural shifts associated with the pursuit of commodification as well as the existence of‘cultures of resistance’, As such, they are viewed as 'spaces of hope’which highlight the demonstrable construction and practice of alternative social relations and logic's of work outside profit‐motivated market‐oriented exchange. 相似文献
8.
Concurrent and longitudinal associations between peer crowd affiliation and internalized distress were examined in a sample of 246 youth (148 girls, 98 boys). Children completed measures of depression, social anxiety, loneliness, and self‐esteem when they were in grades 4 to 6 (Time 1), and again 6 years later during adolescence (grades 10 – 12; Time 2). At Time 2, adolescents also reported their self‐concept and their identification with reputation‐based peer crowds, including Populars, Jocks, Brains, Burnouts, Non‐Conformists, and None/Average crowds. Results indicated that adolescents' report of peer crowd affiliation was concurrently associated with self‐concept and levels of internalizing distress. Follow‐back analyses of internalizing trajectories revealed that Populars/Jocks had experienced significant declines in internalizing distress across development, whereas Brains exhibited some increases in internalizing distress between childhood and adolescence. 相似文献
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10.
THE EAST END, THE WEST END, AND KING'S CROSS: ON CLUSTERING IN THE FOUR-PLAYER HOTELLING GAME 总被引:1,自引:0,他引:1
We study experimentally a standard four-player Hotelling location game with a uniform density of consumers and inelastic demand. The pure strategy Nash equilibrium configuration consists of two firms located at one quarter of the "linear city," and the other two at three quarters. We do not observe convergence to such an equilibrium. In our experimental data we find three clusters. Besides the direct proximity of the two equilibrium locations, this concerns the focal midpoint. Moreover, we observe that whereas this midpoint appears to become more notable over time, other focal points fade away. We explain how these observations are related to best-response dynamics, and to the fact that the players rely on best-responses in particular when they are close to the equilibrium configuration. 相似文献