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121.
Because the item, "How concerned are you about...?" asks respondentsto indicate their level of concern about an issue, some respondentsmay sense it assumes they are concerned or should be concernedabout the issue. Using a filter question to first determineif people are concerned about the issue before asking for theirdegree of concern may help solve this problem. To test thishypothesis, a split-ballot experiment was embedded in a nationalrandom digit dialing telephone survey on food-related issues.For the four items included in the experiment, the group receivingthe filter versions of the questions gave roughly double thepercentages of "not concerned" responses as the group receivingstandard items, and the filter group also gave fewer responsesat the upper end of the response scale.  相似文献   
122.
123.
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   
124.
By the mid-1980s, fertility in most of the world's developed countries had declined to unprecedentedly low levels. Since then, it has declined still further in some, increased slightly in others, and fluctuated in still others. Irrespective of cause, these changes could not have occurred in the absence of substantial control over childbearing.While future increases and decreases are both possible, it is argued that, contrary to the usual demographic expectations for populations exercising substantial control over fertility, fertility in most of these countries will increase to approximate replacement levels and then undergo only minor fluctuations around these levels thereafter.  相似文献   
125.
This examination of emigration dynamics focuses on 13 countries extending from Eritrea to Zimbabwe and Mozambique on the eastern African mainland and on 5 Indian Ocean island nations. The first part of the study looks at the temporal, spatial, and structural perspectives of emigration dynamics. Part 2 considers international migration in the region according to Appleyard's typology (permanent settlers, labor migration, refugees, and illegal migrants) with the additional category of return migration. Measurement issues in emigration dynamics are discussed in part 3, and the demographic/economic setting is the topic of part 4. The demographic factors emphasized include spatial distribution, population density, population structure, population dynamics, demographic transition, and the relationship between internal and international migration. Other major topics of this section of the study are the economic base, the human resource base, population and natural resources, the sociocultural context (emigration, chain migration, return migration, and migration linkages and networks), political factors (including human rights, minority rights and security, regional integration and economic cooperation, and the impact of structural adjustment programs), and a prediction of future emigration dynamics. It is concluded that refugee flows remain a major factor in eastern African countries but the development of human resources in the northern portion of the region indicates development of potential labor migration from this area. Data constraints have limited measurement of emigration in this region and may contribute to the seeming indifference of most eastern African countries to emigration policies. Emigration in this region has been triggered by deteriorating economic and political conditions and is expected to increase.  相似文献   
126.
International migration in eastern and southern Africa (ESA) is rarely addressed in population and development policies or regional organizations, and regional organizations must in the articulation of sustainable shared development identify the role of international migration. Poor quality data on international migration hampers analysis. Sustainable, shared, and human development within the region are subregional issues. Permanent migration is characterized among ESA countries as increasing demographic ethnic pluralism that may result in redrawing of territorial boundaries and further population movement. Portuguese and Arab settlement and integration in eastern areas resulted in coexistence, while European immigration to South Africa resulted in racial segregation. Modern colonial settlement and the aftermath of political conflict resulted in independent countries after the 1960s and outmigration of nonAfrican groups. Much of the labor migration in ESA is unskilled workers moving to South African mining regions. Labor migration to Zimbabwe and Zambia declined after the 1960s. The formation of the Common Market for ESA and the potential merger with the Preferential Trade Area and South African Development Community is a key approach to integration of migration into regional cooperation and shared development. Refugee movements create the most problems. Prior to 1992 ESA countries accounted for 83.4% of refugees, particularly in Mozambique, Ethiopia, and Somalia. Some countries blame poor economic performance on the deluge of refugees. Illegal migration is currently detected because of the required work permits, but the adoption of the Common Market would obscure this phenomenon. Human development is affected most by migrations related to drought, labor migration to strong economic areas, and return migration. The Inter-Governmental Authority on Drought and Development needs to become more active and establish better policies on nomadic and refugee movements and displaced populations. Movement of educated populations to countries lacking in trained and skilled human resources is a future challenge. Strategies of immigration should facilitate economic development.  相似文献   
127.
This article argues that in order to fully understand the geography of labour migration to global cities, it is necessary to consider economic forces in conjunction with mediating socio-cultural influences. Support for this argument is based on an examination of the pattern of migration to Hong Kong, a city which plays a significant role in the world economy.
Reported here are the results of an analysis of recently released 1996 by-census data, and the authors' interviews with foreign domestic workers in Hong Kong. These findings have shown that highly skilled immigrant workers were drawn largely from developed countries, the main sources of inward investment in this city, while less skilled immigrants were drawn from less developed neighbouring labour markets.
While the geographical pattern of immigration followed broadly that predicted from Hong Kong's position in the world economy, the results have revealed that cultural influences such as language and social networks are also important in shaping the economic roles of migrant workers.  相似文献   
128.
129.
This paper develops a model ofinter vivos gifts and bequests in a setting of moral hazard and adverse selection. Altruistic parents do not perfectly know how much effort their children make to earn their living, nor do they know their true level of ability.Inter vivos gifts take place prior to the realization of the children's earnings whereas at the moment of bequests, parents do observe them. We show that an optimal transfer policy generally uses a mix ofinter vivos gifts — deemed as more efficient — and bequests — deemed as more redistributive.We are thankful to Allessandro Cigno, Jacques Cremer, Claude d Aspremont and anonymous referees for their comments.Responsible editor: Alessandro Cigno  相似文献   
130.
Experiments involving large social units, such as schools, work sites, or whole cities, are commonly limited in statistical power because the number of randomized units is small, leaving few degrees of freedom for residual (between-unit) error. The authors describe a method for increasing residual degrees of freedom in a community experiment without substantially increasing cost or difficulty. In brief, they propose that the experimental units should be divided into random subsamples (batches). Batch sampling can improve statistical power if the community endpoint means are stable over time or if their temporal variation is comparable in period to the batch-sampling schedule. The authors demonstrate the theoretical advantages of the batch system and illustrate its use with data from the Pawtucket Heart Health Program, in which such a design was implemented.  相似文献   
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