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As the elderly population of the United States grows in absolute number and as a proportion of total population, accurate projections of that population become increasingly important for sound policy decisions. Cohort component techniques are typically used for state and local projections of the elderly population, but are often outdated or even nonexistent for many local areas. This paper suggests an alternative approach, based on Medicare data and simple projection techniques. Projections for several base periods and projection horizons are made for all states and for counties in Florida and are compared with actual Medicare enrollment. On the basis of these comparisons it appears that Medicare data and simple projection techniques can produce very useful short-run projections of the elderly population for states and local areas.  相似文献   
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本文针对传统方法实现的数字锁相环(DPLL)工作速率低的问题,通过对一种典型的DPLL的分析,找出影响其工作速率的主要因素,研究并提出了一种全新的高速实现方法,并在实验室进行了数据传输位同步提取实验。  相似文献   
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Much of the debate about rising health care costs in the United States centers on the notion of "cost shifting." Cost shifting is loosely defined as charging one set of patients a higher price to offset losses on another set of patients. One aspect of the cost shifting debate that the empirical work has ignored is whether or not doctors—as opposed to hospitals—practice cost shifting. The analysis here investigates this question using the Physicians' Practice Costs and Income Survey, 1983–1985 (PPCIS, expanded version)
Using variation across states in Medicaid reimbursements, the analysis finds that lower Medicaid reimbursements tend to lower the fees physicians charge, contradicting the standard cost shifting story. Evidence also suggests that lower Medicaid reimbursements tend to cause physicians to treat fewer Medicaid patients. These results are consistent with profit maximizing behavior for physicians and also with the hypothesis that physicians exert some monopoly power.  相似文献   
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G. H. BURROWS 《Abacus》1994,30(1):50-64
The extent to which allocated common costs should influence business decisions remains controversial in management accounting. In the finance and investment literature this issue is generally ignored or dismissed by appeals to the'incremental' principle. This article presents an historical analysis of allocations in long-run investing and pricing decisions. It is demonstrated that seminal figures in the development of both investment and price theory were conscious of the need for firms to cover common costs and generally favoured some form of allocation. The anti-allocationist position is shown to be of relatively recent origin and to have caused an inconsistency in the management accounting literature in the treatment of common costs. European costing theory is shown to have been consistently allocationist. Evidence of a return in the recent U.S. literature to the older Anglo-American, and continuing European, allocations tradition is presented.  相似文献   
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Extensification of agriculture is one of the major factors contributing to the destruction of forests in Africa. In Sudan, such horizontal expansion comes at the expense of land devoted to trees and other vegetation, thereby inducing conditions that are inimical to sustainable agricultural production. Different factors have contributed to extensification. Although high economic returns from crop (mainly sorghum) production was an important factor encouraging extensification of rainfed mechanized farming, other factors outside agriculture have also contributed to that expansion. This paper uses data from eastern Sudan and an acreage response model, to identify the most important factors influencing acreage expansion. Different measures and forms of risk were used in the acreage response model. The paper shows how policies in the energy sector can indirectly influence acreage expansion in the agricultural sector.  相似文献   
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