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181.
This article analyzes a 1989 Louis Harris and Associates survey designed to elicit information on the employment histories and job-stopping behavior of men and women who then were approaching or had recently reached retirement age. The results indicate that retirement often occurs gradually and includes a substantial period of "bridge employment." Most bridge jobholders work full-time, by choice, and report high levels of job enjoyment. Occupational mobility occurring late in life typically involves upward movement, although the pattern of change is quite different when it takes place outside, rather than within, the longest job. The principal concern identified in this article is the limited ability of some groups of workers (nonwhites, females, the less educated, and those in poorly compensated occupations) to either retain longest jobs or to obtain acceptable bridge employment. Health problems also frequently lead to early departures from the labor force.  相似文献   
182.
Evolution strategies (ESs) are a special class of probabilistic, direct, global optimization methods. They are similar to genetic algorithms but work in continuous spaces and have the additional capability of self-adapting their major strategy parameters. This paper presents the most important features of ESs, namely their self-adaptation, as well as their robustness and potential for parallelization which they share with other evolutionary algorithms.Besides the early (1 + 1)-ES and its underlying theoretical results, the modern ( + )-ES and (, )-ES are presented with special emphasis on the self-adaptation of strategy parameters, a mechanism which enables the algorithm to evolve not only the object variables but also the characteristics of the probability distributions of normally distributed mutations. The self-adaptation property of the algorithm is also illustrated by an experimental example.The robustness of ESs is demonstrated for noisy fitness evaluations and by its application to discrete optimization problems, namely the travelling salesman problem (TSP).Finally, the paper concludes by summarizing existing work and general possibilities regarding the parallelization of evolution strategies and evolutionary algorithms in general.  相似文献   
183.
Common binary regression models such as logistic or probit regression have been extended to include parametric link transformation families. These binary regression models with parametric link are designed to avoid possible link misspecification and improve fit in some data sets. One and two parameter link families have been proposed in the literature (for a review see Stukel (1988)). However in real data examples published so far only one parameter link families have found to improve the fit significantly. This paper introduces a two parameter link family involving the modification of both tails of the link. An analysis based on computationally tractable Bayesian inference involving Monte Carlo sampling algorithms is presented extending earlier work of Czado (1992, 1993b). Finally, the usefulness of the two tailed link modification will be demonstrated in an example where single tail modification can be significantly improved upon by using a two tailed modification.  相似文献   
184.
Last year, the Internal Revenue Service (IRS) issued Revenue Procedure 93-19 (Rev. Proc. 93-19), which provides guidelines regarding service and other contracts involving facilities financed with tax-exempt bonds. Rev. Proc. 93-19 creates four "safe harbors" for certain contracts signed by tax-exempt organizations that will not jeopardize the organizations' tax-exempt bond interest. Those guidelines and methods for complying with them are the subject of the following article. "Health Law" is a regular feature of Physician Executive contributed by Epstein Becker & Green. Mark Lutes of the law firm's Washington, D.C., offices serves as editor of the column.  相似文献   
185.
A survey was mailed to 100 physician executives identified through the 1991 American College of Physicians Executives directory. The subjects were asked to rate 17 managerial areas on their value to the subjects' current work, on the subjects' preparation in the areas, and on the need for training in the areas. In addition, the subjects were asked how best to accomplish training in the areas and for a list of areas of greatest importance in the future for physician executives. The subjects rated communication skills, quality assurance, utilization review, and personnel management as being of primary value in their current roles. Preparation was most adequate in communication skills and most inadequate in the areas of finance and organizational management. Training was deemed desirable in all areas, but was thought to be most necessary in communication skills, negotiations, strategic planning, and organizational management. There was least desire for training in the areas of labor law and employment law. The most popular means of training were doing a fellowship in administrative medicine, receiving continuing education through seminars or workshops, or getting a degree in management.  相似文献   
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Physicians practicing in large, multispecialty medical groups share an organizational culture that differs from that of physicians in small or independent practices. Since 1980, there has been a sharp increase in the size of multispecialty group practice organizations, in part because of increased efficiencies of large group practices. The greater number of physicians and support personnel in a large group practice also requires a relatively more sophisticated management structure. The efficiencies, conveniences, and management structure of a large group practice provide an optimal environment to practice medicine. However, a search of the literature found no data linking a large group practice environment to practice outcomes. The purpose of the study reported in this article was to determine if physicians in large practices have fewer quality and utilization problems than physicians in small or independent practices.  相似文献   
189.
Recently, the number of physicians who have been interested in alternative careers has vastly increased. Many physicians express dissatisfaction with clinical practice, but they are uncertain about which nonclinical options are appropriate for them. Pursuing a different career after many years of studying and practicing medicine can seem like an overwhelming task. In this article, the author briefly outlines a decision-making process that can be used in analyzing career options and suggests some careers that have provided challenging opportunities for physicians.  相似文献   
190.
The dramatic increase in U.S. cesarean sections over the past two decades has been significantly driven by repeat C-sections. In response to this trend, clinical guidelines recommending vaginal birth after cesarean-section (VBAC) have been promulgated by national organizations. Adherence to these guidelines would reduce the number of repeat C-sections, lower the overall C-section rate, and improve both the quality and the cost of health care. While these guidelines have received professional endorsement, their implementation has been clouded by issues of patient acceptance and provider payment. To examine implementation of these guidelines by health care organizations, the authors surveyed 156 members of the American College of Physician Executives to determine their policies, practices, and attitudes toward VBAC guidelines. Those surveyed generally were medical directors in HMOs, hospitals, and other practice settings. The findings indicate that the health care organizations represented by these physician executives have not consistently implemented VBAC guideline and that they are reluctant to hold physicians, their patients, or hospitals accountable for the financial, utilization, and quality impact of the elective decision ot to pursue appropriate VBACs. We conclude that, even when widely accepted, clinical practice guidelines may be ineffective in reducing the costs or improving the quality of medical care.  相似文献   
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