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201.
This paper studies the notion of coherence in interval‐based dose‐finding methods. An incoherent decision is either (a) a recommendation to escalate the dose following an observed dose‐limiting toxicity or (b) a recommendation to deescalate the dose following a non–dose‐limiting toxicity. In a simulated example, we illustrate that the Bayesian optimal interval method and the Keyboard method are not coherent. We generated dose‐limiting toxicity outcomes under an assumed set of true probabilities for a trial of n=36 patients in cohorts of size 1, and we counted the number of incoherent dosing decisions that were made throughout this simulated trial. Each of the methods studied resulted in 13/36 (36%) incoherent decisions in the simulated trial. Additionally, for two different target dose‐limiting toxicity rates, 20% and 30%, and a sample size of n=30 patients, we randomly generated 100 dose‐toxicity curves and tabulated the number of incoherent decisions made by each method in 1000 simulated trials under each curve. For each method studied, the probability of incurring at least one incoherent decision during the conduct of a single trial is greater than 75%. Coherency is an important principle in the conduct of dose‐finding trials. Interval‐based methods violate this principle for cohorts of size 1 and require additional modifications to overcome this shortcoming. Researchers need to take a closer look at the dose assignment behavior of interval‐based methods when using them to plan dose‐finding studies.  相似文献   
202.
In this paper, we focus on the problem of factor screening in nonregular two-level designs through gradually reducing the number of possible sets of active factors. We are particularly concerned with situations when three or four factors are active. Our proposed method works through examining fits of projection models, where variable selection techniques are used to reduce the number of terms. To examine the reliability of the methods in combination with such techniques, a panel of models consisting of three or four active factors with data generated from the 12-run and the 20-run Plackett–Burman (PB) design is used. The dependence of the procedure on the amount of noise, the number of active factors and the number of experimental factors is also investigated. For designs with few runs such as the 12-run PB design, variable selection should be done with care and default procedures in computer software may not be reliable to which we suggest improvements. A real example is included to show how we propose factor screening can be done in practice.  相似文献   
203.
In Britain in recent years social mobility has become a topic of central political concern, primarily as a result of the effort made by New Labour to make equality of opportunity rather than equality of condition a focus of policy. Questions of the level, pattern and trend of mobility thus bear directly on the relevance of New Labour's policy analysis, and in turn are likely be crucial to the evaluation of its performance in government. However, politically motivated discussion of social mobility often reveals an inadequate grasp of both empirical and analytical issues. We provide new evidence relevant to the assessment of social mobility - in particular, intergenerational class mobility - in contemporary Britain through cross-cohort analyses based on the NCDS and BCS datasets which we can relate to earlier cross-sectional analyses based on the GHS. We find that, contrary to what seems now widely supposed, there is no evidence that absolute mobility rates are falling; but, for men, the balance of upward and downward movement is becoming less favourable. This is overwhelmingly the result of class structural change. Relative mobility rates, for both men and women, remain essentially constant, although there are possible indications of a declining propensity for long-range mobility. We conclude that under present day structural conditions there can be no return to the generally rising rates of upward mobility that characterized the middle decades of the twentieth century - unless this is achieved through changing relative rates in the direction of greater equality or, that is, of greater fluidity. But this would then produce rising rates of downward mobility to exactly the same extent - an outcome apparently unappreciated by, and unlikely to be congenial to, politicians preoccupied with winning the electoral 'middle ground'.  相似文献   
204.
The purpose of the present study was to determine the effectiveness of an ergonomic and behavioral safety intervention for improving participants' safe typing postures in a library office setting. A single-subject multiple baseline design across five participants was employed to evaluate the effects of the four independent variables (workstation adjustment, equipment trial (rollermouse mouse alternative), peer observations, and graphic feedback). Six participant postures were observed repeatedly while participants worked at their workstations throughout the study. Each of the interventions resulted in improvements in safety for more than one posture compared to the previous phase. Results of the study indicate that a comprehensive ergonomic program that includes a workstation adjustment and a behavioral safety approach may be helpful to produce maximum improvements in employees' safe ergonomic postures.  相似文献   
205.
This article reports on a survey of 800 members of four Social HMO demonstration sites, who were receiving home-based, community-based, and short-term institutional services under the demonstration's expanded community care benefits. The survey asked whether members needed help in 11 areas, whether they received help in each area from an informal caregiver, whether they wanted more help from the Social HMO, and whether help provided by both was adequate. Satisfaction with the program and with service coordination was also assessed. The adequacy of informal care differed by problem area, as did the help desired from the Social HMO and its responsiveness. Members were less satisfied when they had weaker informal care, were African American, and when they received inadequate help from the plan with ADLs, transportation, medical access, and managing money. Members were more satisfied when they were professionals, home owners, knew their service coordinator's name (or how to contact her), and received help with their problems. The findings point to the importance of clarifying divisions of labor with informal caregivers, as well as possible expansions in responsibilities for service coordinators and benefits beyond traditional boundaries.  相似文献   
206.
A new version of the age-old controversy between religion and science has been launched by today’s intelligent design movement. Although ostensibly concerned simply with combating Darwinism, this new creationism seeks to drive a “wedge” into the materialist view of the world, originating with the ancient Greek philosopher Epicurus and manifested in modern times by Darwin, Marx, and Freud. Intelligent design proponents thus can be seen as challenging not only natural and physical science but social science as well. In this article, we attempt to explain the long history of this controversy, stretching over millennia, and to defend science (especially social science) against the criticisms of intelligent design proponents – by defending science’s materialist roots.
Brett Clark (Corresponding author)Email:
John Bellamy FosterEmail:
Richard YorkEmail:

Brett Clark   received his Ph.D. from the University of Oregon and is the Editorial Director of Monthly Review Press. His research interests are ecology, political economy, and science. He has published articles and review essays in Theory and Society, The Sociological Quarterly, Organization & Environment, and Critical Sociology. He received the 2007 Outstanding Publication Award from the Environment and Technology Section of the American Sociological Association for a series of articles (one of which was the article “Carbon Metabolism: Global Capitalism, Climate Change, and the Biospheric Rift,” published in Theory and Society in 2005) with Richard York. John Bellamy Foster   is Professor of Sociology at the University of Oregon and editor of Monthly Review (New York). He is the author of The Theory of Monopoly Capitalism (1986); The Vulnerable Planet (1994); “Marx’s Theory of Metabolic Rift,” American Journal of Sociology (1999); Marx’s Ecology (2000); Ecology Against Capitalism (2002); Naked Imperialism (2006); and (with Paul Burkett) “Metabolism, Energy, and Entropy in Marx’s Critique of Political Economy,” Theory and Society (2006). Richard York   is Associate Professor of Sociology at the University of Oregon and co-editor of the Sage journal Organization & Environment. His research focuses on human interaction with the natural environment and the philosophy, history, and sociology of science. He has published articles in American Sociological Review, Gender & Society, Rural Sociology, Social Problems, Social Science Research, Sociological Forum, The Sociological Quarterly, Theory and Society, and other scholarly journals. He has twice (2004 and 2007) received the Outstanding Publication Award from the Environment and Technology Section of the American Sociological Association.  相似文献   
207.
Publishing performance information about local public services,an increasing trend in many Organisation for Economic Co-operationand Development countries, matters politically because it hasan effect on incumbent local governments' electoral support.Voters are able to use performance information to punish orreward incumbents in the elections that follow their publication,which may fill a gap in the chain of accountability betweenvoters and governments. We model the introduction of publishedComprehensive Performance Assessments of local authorities inEngland, which make summary information about performance availableto voters, as a "shock" to the relationship between voters andincumbents. Controlling for an unpublicized measure of performancechange over time, change in the local tax level, change in localeconomic conditions, and whether the local incumbent is theparty of the incumbent government at the national level, wefind negativity bias. Incumbents in local authorities in the"poor" performance category experience a substantial reductionin aggregate vote share at the election following publication,but there is no similarly sized reward for those in the highestperformance category.  相似文献   
208.
209.
Relocation stress syndrome is a nursing diagnosis characterized by symptoms such as anxiety, confusion, hopelessness, and loneliness. It usually occurs in older adults shortly after moving from a private residence to a nursing home or assisted-living facility. The primary purpose of this study was to validate the symptoms of relocation stress syndrome. Eight nursing home residents and 8 assisted-living facility residents were interviewed 2 to 10 weeks after admission, when symptoms of relocation stress syndrome are most likely to appear. Results of this study indicate that the incidence of relocation stress syndrome may be overestimated. More accurate diagnosis and treatment of depression in older adults is needed.  相似文献   
210.
Video recording provides an objective record of the content of medical interactions. However, there is concern that cameras may be reactive measurement devices that alter what normally transpires during interactions. This study addressed potential reactivity of cameras in medical interactions. Interactions between 45 patients and 14 medical oncologists were video recorded and coded for camera-related behaviors. Eleven of 45 patients performed none of the behaviors. Among the other patients, camera-related behaviors were infrequent and, on average, constituted about 0.1% (one-tenth of one percent) of total interaction time. Behaviors occurred most often in very early stages of interactions, and when physicians were absent from the room. Seven physicians showed camera-related behaviors, comprising less than 0.1% of the time they were in the interaction. Results suggest video recording can provide nonreactive means of studying medical interactions.
Louis A. PennerEmail:
  相似文献   
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