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551.
A single latent variable model of health status and therapeutic health care utilization is estimated for parents and own children of 6,557 US households. The equation system that identifies latent health status simultaneously determines a number of indicators of general health, including presence of morbidity symptoms, mobility limitations, medication needs, and utilization of therapeutic health care services. The main goal of the paper was to obtain an unbiased estimate of parents’ marginal substitution rate between own and child health. Results indicate that parents’ valuation of their children’s health exceeds their valuation of own health by almost twofold on average.
Thomas D. CrockerEmail:
  相似文献   
552.
This article uses a demographic approach and data from the Health and Retirement Survey, a nationally representative sample of the U.S. population, to investigate sex differences in the length of life lived with heart disease and after a heart attack for persons in the United States age 50 and older. On average, women live longer than men with heart disease. At age 50 women can expect to live 7.9 years and men 6.7 years with heart disease. The average woman experiences heart disease onset three years older and heart attacks 4.4 years older than men.  相似文献   
553.
An ecological evolutionary viewpoint offers new perspectives on contemporary demographic problems in general and on population–environment issues in particular. In turn, rich and detailed human demographic data can help solve problems of interest in evolutionary theory. Such data have been analyzed in greatest detail in studies of traditional and historical societies. Evolutionary approaches using historical data go beyond small‐sample anthropological studies to the application of the evolutionary approach to large datasets, and illuminate important similarities between small‐scale traditional societies and large modern populations living in evolutionarily novel environments. This article provides a concise update of the breadth of questions and hypotheses of likely interest to demographers and others that evolutionary theorists address using a variety of traditional and historical datasets. It suggests opportunities for additional collaborative work between evolutionary theorists and historical demographers and highlights topics relevant to modern demography.  相似文献   
554.
Indonesia's family planning program is regarded as a major success.Survey data from 1997 reveal that rates of contraceptive use vary dramatically amongIndonesia's 27 provinces, from a high of 67 percent of ever married women currently using contraceptives in the province of North Sulawesi, to a low of 19 percent current users in East Timor and28 percent in Aceh. This study uses both a quantitative analysis of the 1997 Indonesia Demographic and Health Survey, and a qualitative study carried out in July of 2000 to understand regionalvariation. The study identified a small number of factors that show a clear relation with levels of contraceptive use. Media exposure and education are the strongest and most consistent predictors of levels of contraceptive use, and appear to be the surest strategies for promoting family change. But the study also showed that the process of social change is subjectto culturally and historically specific local factors whose presence and importance is difficult to predict. Our study of regional variation in contraceptive use illustrates the range and complexityof obstacles faced by Indonesia's leaders in attempting to forge a single nation fromsuch a diverse and far-flung population. Although the creation of Indonesia in the space of just half a century is a monumental achievement, the project is clearly not yet complete.  相似文献   
555.
This paper examines a wide variety of forms, and full histories, of family structure to test existing theories of family influences and identify needs for new theories. The focus is on links between childhood family structure and both completed schooling and risk of a nonmarital birth. Using a 27-year span of panel (PSID) data for U.S. children, we find that: (a) change is stressful, (b) timing during childhood is relevant, (c) adults other than parents are important, and (d) two more recently studied family structures (mother-with-grandparent(s) and mother-with-stepfather) do not fit the molds of existing theories. The findings suggest that new theories should consider allocation of resources and reasons people group into family structures. Received: 11 September 1998/Accepted: 27 March 2000  相似文献   
556.
Previous studies have found that educational differences in mortality are weaker among the elderly. In this study I examine whether either cohort or period effects may have influenced the interpretation of age effects. Six 10-year birth cohorts are followed over 30 years through decennial censuses. Differential survival is inferred from changes in the relative proportions of a cohort in each education category as the cohort ages. In cross-section, younger persons generally show stronger education effects on survival, although this pattern is clearer for women than for men. There is evidence of period effects. Within cohorts, relative survival tends to increase with age.  相似文献   
557.
Lori S. Franz 《决策科学》1989,20(4):830-843
The teaching of decision sciences presupposes that careful attention is directed toward improving students' critical thinking and analytical skills. This paper presents an approach to teaching quantitative methods classes that focuses on developing student skills in the areas of analytical and critical thinking through written and oral communication. The approach requires very little additional instructor preparation time and does not require the instructor to make major changes in either the content or organization of the course. While the instructor's investment is minimal, the benefits to the students appear to be substantial.  相似文献   
558.
Certain motor vehicle safety standards stipulate a collision test speed and a set of performance criteria that vehicles must satisfy during or after the collision test. For example, Federal Motor Vehicle Safety Standard 301 requires a 30 mile per hour (mph) barrier collision and specifies a certain maximum allowable limit on the total spillage of fuel. Vehicle designs are required to meet this standard; however, when collision tests are conducted at speeds higher than the standard, vehicles do not always satisfy the performance criteria. This paper develops a mathematical model for estimating the probability of meeting the standard by using a Bayesian framework to incorporate engineering judgment with collision test results. The model is based on the idea that there are random features to a vehicle's ability to meet performance standards in a collision, especially at such elevated speeds. Example calculations are included to illustrate the estimation of the probability of meeting the standard and to compare it with a maximum likelihood approach.  相似文献   
559.
In a recent paper, Pinto and Mabert [5] presented a lot-sizing rule and an improvement procedure for the joint lot-sizing problem with zero setup costs. We show that this procedure often yields infeasible schedules. We also present and discuss two interesting properties of the joint lot-sizing problem with zero setup costs. A numerical example to illustrate the second property is provided.  相似文献   
560.
Lori S. Franz 《决策科学》1989,20(2):359-377
This paper presents a data driven modeling (DDM) approach to certain types of optimization problems. DDM relinquishes control of the completed model to the user department rather than the operations research (OR) staff. The approach emphasizes development of models that are dependent on data maintained and understood by the users. The data base consists of coded user rules which describe when changes will occur in the problem structure and data which captures the generalization of the problem. Both the rules and data can be updated by user department personnel. These data drive a matrix generator controlled by the rules which uses the data base as input to generate the specific model formulation. This DDM system is designed by OR consultants or staff to allow independence of use along with low-cost and minimal-effort maintenance. The DDM approach is illustrated with an application to a real-world medical scheduling problem.  相似文献   
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