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71.
In this paper, the task of determining expected values of sample moments, where the sample members have been selected based on noisy information, is considered. This task is a recurring problem in the theory of evolution strategies. Exact expressions for expected values of sums of products of concomitants of selected order statistics are derived. Then, using Edgeworth and Cornish-Fisher approximations, explicit results that depend on coefficients that can be determined numerically are obtained. While the results are exact only for normal populations, it is shown experimentally that including skewness and kurtosis in the calculations can yield greatly improved results for other distributions.  相似文献   
72.
1. Several factors may affect an elderly client's use of medications: polypharmacy, potentially leading to interactions; over-the-counter drugs taken without a physician's knowledge; noncompliance or poor compliance with medication regimens; and ageist beliefs. 2. Psychiatric nurses must be aware that the signs and symptoms they observe may be the result of normal physical or biological aging, psychosocial changes, disease-related changes, medication side effects, or a drug interaction. 3. Nurses must ask two questions when psychotropic drugs are used with elderly clients: What will be the onset, duration, magnitude, and characteristic action of a specific drug in an individual; and What are the characteristics of an "ideal" medication?  相似文献   
73.
A paradox currently exists regarding legal sports gambling in North America: various forms are flourishing in Nevada, Oregon, and several Canadian provinces, while at the same time the United States Congress is conducting hearings on two bills that would prohibit any new state-sponsored sports gambling initiatives. This study examines the issue of why some jurisdictions are enthusiastic about legal sports gambling while others strongly resist the concept. In reviewing these divergent viewpoints, a case study of the newfledged Canadian Sport Select gambling format is presented. This example is used to highly the perils and payoffs of a typical state-sponsored sports gambling scheme, with a view toward broadening our understanding of how they work and how they might be fairer to the public.  相似文献   
74.
Originally presented to the Society of Home Health Care Management of the American College of Physician Executives at its November 16, 1993, meeting in Tucson, Ariz., the program described in this article was the winner of the College's 1994 Innovations Award in Medical Quality Management, sponsored by Merck Sharp & Dohme. The program shows the potential of case management for both improvement in the quality of care and containment of costs for a managed care population with a substantial Medicaid segment. This article is part of a continuing series on innovative programs in home health care.  相似文献   
75.
An evaluation of population projection errors for census tracts   总被引:1,自引:0,他引:1  
"In this article we evaluate the accuracy and bias of projections of total population and population by age group for census tracts in three counties in Florida. We use [U.S. census] data from 1970 and 1980 and several simple extrapolation techniques to produce projections for 1990; we then compare these projections with 1990 census counts and evaluate the differences. For the total sample, we find mean absolute errors of 17%-20% for the three most accurate techniques for projecting total population and find no indication of overall bias. For individual age groups, mean absolute errors range from 20%-29%." This is a revised version of a paper presented at the 1993 Annual Meeting of the Population Association of America.  相似文献   
76.
The World Health Organization (WHO) diagnostic criteria for diabetes mellitus were determined in part by evidence that in some populations the plasma glucose level 2 h after an oral glucose load is a mixture of two distinct distributions. We present a finite mixture model that allows the two component densities to be generalized linear models and the mixture probability to be a logistic regression model. The model allows us to estimate the prevalence of diabetes and sensitivity and specificity of the diagnostic criteria as a function of covariates and to estimate them in the absence of an external standard. Sensitivity is the probability that a test indicates disease conditionally on disease being present. Specificity is the probability that a test indicates no disease conditionally on no disease being present. We obtained maximum likelihood estimates via the EM algorithm and derived the standard errors from the information matrix and by the bootstrap. In the application to data from the diabetes in Egypt project a two-component mixture model fits well and the two components are interpreted as normal and diabetes. The means and variances are similar to results found in other populations. The minimum misclassification cutpoints decrease with age, are lower in urban areas and are higher in rural areas than the 200 mg dl-1 cutpoint recommended by the WHO. These differences are modest and our results generally support the WHO criterion. Our methods allow the direct inclusion of concomitant data whereas past analyses were based on partitioning the data.  相似文献   
77.
Author of the highly acclaimed Borrowed Time: An AIDS Memoir (1988) and winner of the 1992 National Book Award for his autobiography Becoming a Man: Half a Life Story, Paul Monette died of complications from AIDS in Los Angeles on February 12, 1995. His most recent work, Last Watch of the Night: Essays Too Personal and Otherwise (1994), is his third volume in a trilogy of autobiographical writing on growing up gay, coming-out, and living with AIDS. A graduate of Phillips Academy and Yale University, Monette received a number of awards for his writing and his work as an outspoken voice in the battle against AIDS, including the National Book Award, three Lambda Literary awards, the PEN Center West Freedom to Write Award, and three honorary doctorate degrees, from Wesleyan University, the City University of New York, and the State University of New York at Oswego. A memorial service was held for Monette on Sunday, February 19, 1995, at the Directors Guild of America on Sunset Boulevard in Los Angeles. Paul Monette was 49.  相似文献   
78.
A measure of range of ability is used to profile the 85-years-old-and-older (oldest old) population, including the highly disabled institutional population. This new measure uses two new questions available in the 1990 Decennial Census concerning a self-care limitation and a mobility limitation as well as the usual question concerning a work limitation. In addition to examining the extent of disability among the oldest old, the article examines the extent of care potentially available in the household as well as the economic characteristics of this age group. It is also profiled in terms of relevant personal characteristics, including age, gender, marital status, race, ethnicity, rural residence, education, and employment. A key question addressed is the need for help or care among the oldest old and how various long-term care proposals would meet such needs. A careful analysis of this unique and growing population is necessary to both allay fears of the cost of care or help as well as to dispel stereotypes of this age group as frail and dependent, and in need of institutional care.  相似文献   
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