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171.
This paper studies two models of rational behavior under uncertainty whose predictions are invariant under ordinal transformations of utility. The quantile utility model assumes that the agent maximizes some quantile of the distribution of utility. The utility mass model assumes maximization of the probability of obtaining an outcome whose utility is higher than some fixed critical value. Both models satisfy weak stochastic dominance. Lexicographic refinements satisfy strong dominance.The study of these utility models suggests a significant generalization of traditional ideas of riskiness and risk preference. We define one action to be riskier than another if the utility distribution of the latter crosses that of the former from below. The single crossing property is equivalent to a minmax spread of a random variable. With relative risk defined by the single crossing criterion, the risk preference of a quantile utility maximizer increases with the utility distribution quantile that he maximizes. The risk preference of a utility mass maximizer increases with his critical utility value.  相似文献   
172.
173.
The age structure of a population is one basic factor of population research. It is not only affected by birth, death, immigration, and marriage, but it also reflected in changes of family size. The article analyzed it from two aspects: (1) the age structure of population acts on the size and structure of the family. The younger the age structure, the larger the family size. Otherwise, it is the opposite. According to the 1982 census, 35.4% of the population was 0-14 years in rural areas, and average family size was 4.6; but in urban areas 26.0% of the population was 0-14 years and family size was 3.9. The family was characterized as a nuclear family as industrialization in economic development increased and the population aged. In the 1982 census, 64.7% were nuclear family and 6% were aging population in China. Three- generation families (or more) have decreased dramatically. The change of family size and structure is affected by change of internal family age structure. The younger population (0-14 years) is dependent and 90% live with their parents. The adult population (15-59) years are more affected by marriage, birth and social economic action. Families are established in this age period and give much more effect to fertility. The aging population (over 60) years is facing changes. They appear to be a "Defect" family because the wife or husband has passed away. They change from independent to dependent. 78.3% population over 60 years were dependent on children or social welfare, only 21.7% were independent according to the survey in Beijing Changping County.  相似文献   
174.
"This study examines the relationship between black population concentration (% black), black population change and white population change for small American suburbs for the 1950-1980 period. Linear, tipping point (curvilinear) and interaction models of racial transition are evaluated for each decade by region (South and non-South), controlling for several other suburban characteristics (age, annexation and distance to the Central Business District) which may affect both black and white population change. The analyses show that racial transition in suburbs involves the parallel development of white and black populations with mainly weak and complex causal linkages which are sensitive to broader suburbanization patterns."  相似文献   
175.
The medical model as a conceptual and operative approach to compulsive gambling is discussed. The terms medical model and disease are defined and the practical implications of their application to compulsive gambling are explored. Special attention is given to the addictive disease concept. Finally, a variety of objections to the medical model are described, but it is concluded that the many individual and social advantages of the medical model make it the preferred conceptualization at our present state of knowledge.  相似文献   
176.
A questionnaire was designed to test selected aspects of the author's General Theory of Addictions (Jacobs, 1982). Data were collected from groups of compulsive gamblers, alcoholics, and compulsive overeaters, and compared with the responses to the same questionnaire obtained from normative samples of adolescents and adults. The more inclusive term, compulsive gambler, has been used throughout, since the sample of gamblers in this study included an inpatient subgroup who had been diagnosed as pathological gamblers, as well as a subgroup of Gamblers Anonymous members who had not been clinically evaluated. Findings support the author's theoretical position that, when indulging, different kinds of addicts will tend to share a common set of dissociativelike experiences that differentiate them from nonaddicts. This has been termed a state of altered identity.  相似文献   
177.
Continued economic stagnation, civil unrest, rural-urban migration, and a series of natural disasters have impeded efforts in the Sudan to integrate women into the development process. Although the Four-Year (1988-1989 to 1991-92) Salvation, Recovery, and Development Programs Plan does not explicitly addresses women's issues, its emphasis on food security, appropriate technology for the agricultural sector, small-scale industries and handicrafts, balanced regional development, and the needs of the poorest 20% of the population guarantees that women will be major recipients. There remains a need, however, to increase women's participation in the development planning process and to base projects on reliable data on women's economic activities. More successful in defining women's needs have been community development projects--Western Savannah Development Corporation, Blue Nile Integrated Rural Development Project, Nuba Mountain Project, and Jebel Marra Rural Development Project--that combine income generation, social welfare, and agricultural research. It is recommended that all such large integrated rural development or agricultural projects allot funds specifically for women's activities and ensure coordination with women's organizations to avoid duplication and identify areas of greatest need. Also urged is the development of appropriate technologies that will alleviate women's double burden of poverty and household chores and address the inequitable distribution of income. Establishment of a women's bureau for women's affairs and development within the National Planning Department would facilitate project formulation and evaluation. In need of change if women in development projects in the Sudan are to be successful are laws that limit female land ownership and practices that deny women loans and credit.  相似文献   
178.
A comparative study conducted in the Sudan illustrated both the potential of a nutrition education program for pregnant women and the many obstacles to creating more optimal maternal nutrition. Included in the study were 1200 women 18-34 years of age attending the Khartoum Province Model Clinic for a minimum of 5 prenatal visits. 83.3% were Muslims and 48.2% were illiterate. The 60 women who comprised the experimental group were exposed to individual nutrition counseling and home visits. Overall, 70% of subjects were anemic, 27% had malaria, and 18% were hookworm. The average weight gain during pregnancy was 4.5 kgs; 25.0% of controls and 20.0% of those in the experimental group gained 3.5-4.0 kgs, 18.3% of controls and 33.3% of experimental subjects gained 4.5-5.0 kgs, and 23.3% of controls and 30.0% of those in the experimental groups gained 5.5 kgs or more. 53.0% of controls and 61.7% of women exposed to nutrition education breastfed for at least 6 months, and 70% of women in the former group and 95% of those in the latter had enrolled their infants in an immunization program. A baseline nutrition questionnaire revealed widespread misinformation, especially a belief that pregnant women should reduce their food intake from 3 to 1-2 meals per day to prevent the fetus from growing too large and making labor difficult. Foods such as fermented sorghum products, fresh fish, and water melon were regarded as abortifacients and avoided, while hot pepper, sour milk, and cola sodas were considered nutritious. Consumption was self-reported to be poor for milk products by 25% of mothers, for meat by 16%, and for fruits and vegetables by 40% Although the educational intervention increased women's knowledge of basic nutrition, it had only a minimal effect on actual practice. This finding is assumed to reflect the widespread belief that men and their guests should be given preference in food allocation, poverty, and avoidance, on the basis of tradition, of many healthy foods. Since 72% of women reported ownership of a television, use if this medium is recommended for nutrition education.  相似文献   
179.
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   
180.
1. As the nurse-patient relationship evolves through a series of ongoing interactions, both participants become "known" and stir in each other a range of positive and negative emotional reactions. 2. When working with severely psychologically disturbed patients, the nurse's affective and behavioral response can be valuable clues to understanding the patient's early experiences that contribute to the pattern of relatedness and to the formulation of change, enhancing therapeutic interactions. 3. The goals of the countertransference peer supervision group were to recognize unconscious countertransference reactions; unravel the origin and meaning of those countertransference reactions; and collaboratively develop therapeutic nursing interventions.  相似文献   
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