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81.
82.
This study uses qualitative and quantitative measures to answer the question: “does a community development financial institution (CDFI) provide a measurable level of social benefit to its members?” Results indicate that a CDFI does change lives in many important ways, from providing members with the ability to get their financial houses in order, to helping members take control of their financial futures, and finally through building a sense of empowerment that reaches beyond the finances of an individual or family. In general, impacts were greater for lower income and less educated households, households with children, households that used more services, and for households that indicated wealth and asset building services were most important.  相似文献   
83.
The objective study of self‐recognition, with a mirror and a mark applied to the face, was conducted independently by Gallup (1970) for use with chimpanzees and monkeys, and by Amsterdam (1972) for use with infant humans. Comparative psychologists have followed the model (and assumptions) set by Gallup, whereas developmental psychologists have followed a different model (e.g., Lewis & Brooks‐Gunn, 1979). This article explores the assumptions in the definitions and methods of self‐recognition assessments in the 30 years since these initial studies, and charts the divergence between the developmental mark test and the comparative mark test. Two new studies, 1 with infant chimpanzees and 1 with infant humans, illustrate a reconciliation of the 2 approaches. Overt application of the mark, or other procedures related to how the mark is discovered, did not enhance mirror self‐recognition. In contrast, maternal scaffolding appears to enhance performance, perhaps by eliciting well‐rehearsed verbal responses (i.e., naming self). When comparable testing procedures and assessment criteria are used, chimpanzee and human infants perform comparably. A combined developmental comparative approach allows us to suggest that mirror self‐recognition may be based on a specific aspect of mental representation, the cognitive ability to symbolize.  相似文献   
84.
Markers, which are prognostic longitudinal variables, can be used to replace some of the information lost due to right censoring. They may also be used to remove or reduce bias due to informative censoring. In this paper, the authors propose novel methods for using markers to increase the efficiency of log‐rank tests and hazard ratio estimation, as well as parametric estimation. They propose a «plug‐in» methodology that consists of writing the test statistic or estimate of interest as a functional of Kaplan–Meier estimators. The latter are then replaced by an efficient estimator of the survival curve that incorporates information from markers. Using simulations, the authors show that the resulting estimators and tests can be up to 30% more efficient than the usual procedures, provided that the marker is highly prognostic and that the frequency of censoring is high.  相似文献   
85.
Food safety objectives (FSOs) are established in order to minimize the risk of foodborne illnesses to consumers, but these have not yet been incorporated into regulatory policy. An FSO states the maximum frequency and/or concentration of a microbiological hazard in a food at the time of consumption that provides an acceptable level of protection to the public and leads to a performance criterion for industry. However, in order to be implemented as a regulation, this criterion has to be achievable by the affected industry. In order to determine an FSO, the steps to produce and store that food need to be known, especially where they have an impact on contamination, growth, and destruction. This article uses existing models for growth of Listeria monocytogenes in conjunction with calculations of FSOs to approximate the outcome of more than one introduction of the foodborne organism throughout the food-processing path from the farm to the consumer. Most models for the growth and reduction of foodborne illnesses are logarithmic in nature, which fits the nature of the growth of microorganisms, spanning many orders of magnitude. However, these logarithmic models are normally limited to a single introduction step and a single reduction step. The model presented as part of this research addresses more than one introduction of food contamination, each of which can be separated by a substantial amount of time. The advantage of treating the problem this way is the accommodation of multiple introductions of foodborne pathogens over a range of time durations and conditions.  相似文献   
86.
General Motors had enjoyed global operations that were based on exports, acquisitions, joint ventures and strategic alliances throughout the 20th century. Its global-programme strategy appeared assured. However, the carmaker came unstuck when it came to creating a large-scale collaborative effort involving its own internal units. The Delta Small Car Program, involving three fully internal GM units, was terminated after its goals failed to materialise. The carmaker’s long-standing cultural tradition of autonomy for its units was what made collaboration between them difficult. We examine this GM global programme, placing it in its historical context. Our primary database consists of the perceptions and experiences offered to us by a cross-section of programme participants. By examining partner integration at the working level, we identify insights and offer recommendations pertaining to venture structure and dynamics and their role in venture success.  相似文献   
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This article outlines the development of evaluative methods within the field of mental handicap services. It suggests that evaluators have too often taken for granted the tacit assumptions underlying service models, using these to determine the criteria for evaluating success. It argues that evaluators should be more explicit about the values they adopt, and what patterns of life services should be enabling people to achieve. By more closely linking evaluation criteria to what people with a mental handicap should achieve, evaluation can become more effective in promoting positive change in service models. The article describes an approach developed by the authors for the evaluation of the 'All-Wales Strategy for the Development of Services for Mentally Handicapped People'.  相似文献   
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90.
Stewart D Hodges 《Omega》1976,4(6):699-709
This paper discusses a number of problems which arise in the implementation of portfolio selection models. It is suggested that the effect of errors and biases in expected return forecasts can be reduced by using these forecasts to modify a prior distribution which leads to minimal trading activity. Efficient diversification across industry groups is hampered by the difficulties of predicting covariances. The use of a selection model through time raises the issues of revising forecasts and of the relationships upon which the appropriate investment horizon and portfolio turnover depend. Last, consideration is given to the conflicts which may exist between management objectives and the mean-variance criterion used by most models.  相似文献   
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