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941.
In this study the potential performance benefits of easy goals were examined within the multiple cue probability learning paradigm (MCPLP). Specifically, the effects of varying levels of goal difficulty on performance and risk propensity (used to define a form of commitment) were investigated. With few exceptions, previous studies demonstrated support for difficult goals. In this study, contrary to the majority of past evidence, as goals became easier decision quality significantly improved. Moreover, risk propensity increased with easier goals and, as suggested by a post-hoc analysis, had more direct impact on decision makers’ behaviors than goal levels. Goal-related behavior in complex MCPLP tasks appears to significantly differ from the majority of goal evidence in other types of research due to the tendency for subjects to view complex task properties in the same context as goal levels. 相似文献
942.
In an earlier paper [11], the problems of rank reversals and invalid composite priorities in AHP were addressed by modifications to the AHP procedure. That solution was subsequently criticized [5]. In this paper, we rebut these criticisms, and we show how rank reversals in AHP can arise merely from the process of normalizing local priorities. 相似文献
943.
Constrained forecasting has become a popular approach to the complex task of predicting future sales. Mixed performance results have been obtained by companies employing constrained forecasting systems software packages which probably reflects the lack of any clear system implementation guidelines. A number of important operational parameters such as the number of product families, criterion used to define product families, number of system levels, etc. must be specified. This study reports on an investigation of two of these parameters: product group size and appropriate grouping criterion. Different tests are performed with the constrained forecasting system and compared to a traditional forecasting approach using product data from the Cummins Engine Company of Columbus, Indiana. 相似文献
944.
This study revisits the traditional single stage, multi-item, capacitated lot-sizing problem (CLSP) with a new integrative focus on problem structuring. Unlike past research, we develop integrative cycle scheduling approaches which simultaneously address lot-sizing, capacity, and sequencing issues. Our purposes are to (1) explore the effect of sequencing on inventory levels, (2) examine the problem of infeasibility in the economic lot scheduling problem (ELSP), and (3) provide a simple methodology of generating low-cost cycle schedules in an environment with discrete shipping, dynamic demands, limited capacity, zero setup cost, and sequence-independent setup times. Our procedures are compared to benchmark cycle scheduling approaches in terms of both inventory cost and computation time under different demand scenarios, using the operating data from a flexible assembly system (FAS) at the Ford Motor Company's Sandusky, Ohio plant. 相似文献
945.
Scheduling in a Management Context: Uncertain Processing Times and Non-Regular Performance Measures*
Decision makers often face scheduling problems in which processing times are not known with certainty. Non-regular performance measures, in which both earliness and tardiness are penalized, are also becoming more common in both manufacturing and service operations. We model a managerial environment with task processing times (which include sequenceindependent set-up times) prescribed by three-parameter lognormal distributions. Upon completion, each task derives a reward given by a particular piecewise-linear reward function. The objective is to select a sequence of tasks maximizing the expected total reward. The relative generality of the problem renders many enumerative methods inapplicable or computationally intractable. To overcome such difficulties we develop efficient priorityinduced construction (PIC) heuristics which build up a complete schedule by inserting tasks (singly from a list) into a partial sequence of tasks. In each partial and complete sequence a period of idle time is permitted prior to the first task. Performance on realistic-sized problems is very encouraging, with cost penalties averaging less than one percent. 相似文献
946.
一刘智的《天方性理》是18世纪和19世纪期间中国穆斯林最为广泛阅读的书之一,但该书后来逐渐为某些穆斯林学者所批评。批评此书的穆斯林学者认为,它从真正的伊斯兰教那里走岔了道。即便在今天,那些读此书的穆斯林或非穆斯林们都为这样的事实所触动,即它与通常描述的伊斯兰教义不完全相像。他们多半会问:这本书如何谈论伊斯兰教的呢?哪些地方被认为是穆斯林的内容呢?比如从《古兰经》、先知穆罕默德和大权威作家那里引用的内容在哪里?礼仪的教导、教规和制度、穆斯林信仰的认主学阐述又在哪里呢?为什么会有如此多的新儒家专用术语?从笔者这方… 相似文献
947.
Social Indicators Research - The income inequality hypothesis claims that in rich societies inequality causes a range of health and social problems (henceforth: social ills), e.g. because economic... 相似文献
948.
949.
Sarah A. Font Elizabeth T. Gershoff 《Social policy report / Society for Research in Child Development》2020,33(3):1-40
Foster care provides round-the-clock substitute care for nearly 700,000 U.S. children who are temporarily or permanently separated from their family of origin each year. Each state manages its own foster care system according to federal regulations. Despite numerous large-scale federal policy reforms over the past several decades, substantial concerns remain about the experiences and outcomes of children in the foster care system. The most recent effort to reform foster care, the Family First Prevention Services Act of 2018, attempts to both reduce the use of foster care and increase the quality of care. In this report, we review how policy has shaped the experiences and outcomes of children in foster care, where policy has succeeded, and where it falls short of achieving its goals. We then identify opportunities for federal and state policy to better support the safety, health, and well-being of children in foster care. 相似文献
950.
Katherine J. Curtis Jack DeWaard Elizabeth Fussell Rachel A. Rosenfeld 《Rural sociology》2020,85(4):856-898
Places affected or threatened by extreme environmental disturbances confront a number of significant issues, including whether their populations will stay the same or change through migration. Research on Hurricanes Katrina and Rita shows some displaced residents returned to their disaster-affected communities once the built environment was restored, new migrants settled in affected places as part of the rebuilding effort, and the regional migration system grew more urbanized and spatially concentrated during post-disaster years. Research also shows that not all disaster-affected places recovered their populations. Our study examines whether differential recovery is systematically patterned along the rural–urban gradient. Using U.S. Census Bureau estimates and IRS county-to-county migration data, we investigate whether the 2005 hurricane season differentially exacerbated or altered previous migration trends across a rural–urban gradient that incorporates proximity to metropolitan areas and disaster-related housing loss. We find a rural–urban differential in Gulf Coast recovery migration: The disaster boosted migration among non-metropolitan counties, yet these increases were smaller and short-lived compared to the patterns found for metropolitan counties, most especially high loss metropolitan counties. Our findings encourage theories of environmental migration to incorporate spatial differentiation and scenarios of environmental changes to account for differential impacts on settlement patterns across the rural–urban continuum. 相似文献