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991.
This review of current knowledge about emigration dynamics from and within South Asia (Bangladesh, India, Pakistan, and Sri Lanka) opens with a brief history of the three phases of emigration from the area since the 1830s (plantation labor; postindependence to the UK, US, Canada, and Australia; and labor migration to the oil-exporting countries). The influence of the creation of Pakistan and Bangladesh is also covered as are British colonial and commonwealth policies. It is noted that migration data are incomplete and that India exhibits an ambivalence about collecting such information. The discussion then turns to emigration since 1970 and considers permanent migration from South Asia to the traditional receivers; South Asian asylum seekers in Europe; South Asian refugees, illegal migrants, migrant workers (flows and destinations), the stock of contract migrant workers (and their characteristics); returnee migrant workers; and skill levels. Analysis is provided of macro level determinants of emigrations such as gross national product (level and growth), the general demographic and social situation, labor force growth and structure, poverty and inequality, and internal and international migration. Environmental factors causing displacement in Southern Asia include floods, cyclones, river bank erosion, drought, and desertification. Global warming could displace millions of people in the region, and development projects have contributed to displacement. The remainder of the report covers political and ethnic factors, micro-factors influencing migration decision-making, the policies of sending and receiving countries, the consequences of emigration, and the potential for migration in the future.  相似文献   
992.
This paper introduces a drawing technique developed by the author for use in the assessment and treatment of individuals and families. The client is invited to draw a floor plan of his or her home or apartment, or an aerial view of un outdoor area. The drawing is then discussed and considered as a means of understanding critical elements of the experience of life space. The material derived is discussed from the eerspectives of family systems, psychodynamic, and abuse treatment theories, with special reference to notions of family structure, boundary, the self, and memory. Emphasis is placed on the actual physical layout of the home, as well as the subjective experience of it. Applications of the drawing technique for exploring memories are illustrated. Case examples are presented from clinical trials with children and adults in residential treatment, inpatient, and outpatient settings.The Heller Financial Corporation generously supports the development of household and spatial drawings for treatment and prevention. A version of this paper was presented at the 43rd Annual Meeting of the American Association of Psychiatric Services for Children, New Orleans, February 26, 1992. The author wishes to thank Robert B. Bloom, Ph.D., Excutive Director of JCB, for supporting the development of ideas and techniques discribed in this paper.  相似文献   
993.
Suppose that social welfare function f satisfies the Pareto condition and has complete and transitive values. On a domain satisfying the free quadruple property, if the outcome set X has m< outcomes, then the set of pairs of distinct alternatives on which f satisfies both independence and nondictatorship contains at most the fraction 2/m of all pairs. On a domain satisfying the free six-tuple property, if X is a subset of Euclidean space then the set of pairs on which f satisfies both independence and nondictatorship has Lebesgue measure zero.Campbell's research was financed by the National Science Foundation, grant SES 9209039.  相似文献   
994.
This study is based on interviews with grandmothers during July-September 1992-93 in Sudan. The study shows that grandmothers play a significant role in health education and child care within families in the Sudan. Grandmothers, who are not aware of the changes in knowledge, also promote harmful traditions. The authors recommend that health education be directed to elderly women and grandmothers in order to change beliefs and practices that continue to be harmful to children and mothers. Grandmothers were found to give sound advice on child birth, such as movement during labor, breast feeding immediately after birth, and birth intervals of 2-4 years. Grandmothers also gave sound advice on good nutritional practices during pregnancy and use of fermented cereals as weaning foods. Grandmothers recommended use of fenugreek for lactating mothers and use of mint and haharaib for stomach upsets, remedies that are beneficial. Babul is useful after an episiotomy for its antibacterial effects. Harmful advice includes recircumcision after delivery, short birth intervals, and avoidance of contraception. Female genital mutilation (FGM) is a major practice that exposes girls and mothers to a greater risk of mortality during childbirth and pregnancy. The sample of grandmothers agreed on the importance of sex education for a girl before marriage. Unfortunately, 57% of grandmothers recommended 14 years as a suitable age for marriage. Grandmothers generally believed wrongly that riding bicycles, drinking coffee, and wearing trousers by girls would increase their sexual desires. Grandmothers explained menstruation to granddaughters and offered home-made remedies for cramps. 45% believed that there were no disadvantages to FGM and recommended FGM at ages 2-5 years. Most viewed fevers as a danger that required a doctor's care. Advice varied among grandmothers according to socioeconomic class.  相似文献   
995.
Consider a randomized trial in which time to the occurrence of a particular disease, say pneumocystis pneumonia in an AIDS trial or breast cancer in a mammographic screening trial, is the failure time of primary interest. Suppose that time to disease is subject to informative censoring by the minimum of time to death, loss to and end of follow-up. In such a trial, the censoring time is observed for all study subjects, including failures. In the presence of informative censoring, it is not possible to consistently estimate the effect of treatment on time to disease without imposing additional non-identifiable assumptions. The goals of this paper are to specify two non-identifiable assumptions that allow one to test for and estimate an effect of treatment on time to disease in the presence of informative censoring. In a companion paper (Robins, 1995), we provide consistent and reasonably efficient semiparametric estimators for the treatment effect under these assumptions. In this paper we largely restrict attention to testing. We propose tests that, like standard weighted-log-rank tests, are asymptotically distribution-free -level tests under the null hypothesis of no causal effect of treatment on time to disease whenever the censoring and failure distributions are conditionally independent given treatment arm. However, our tests remain asymptotically distribution-free -level tests in the presence of informative censoring provided either of our assumptions are true. In contrast, a weighted log-rank test will be an -level test in the presence of informative censoring only if (1) one of our two non-identifiable assumptions hold, and (2) the distribution of time to censoring is the same in the two treatment arms. We also extend our methods to studies of the effect of a treatment on the evolution over time of the mean of a repeated measures outcome, such as CD-4 count.  相似文献   
996.
A controlled exit-poll experiment on Election Day (November3, 1992) shows that refusals to answer questions and other evasiveforms of responding were significantly lower when respondentswere given a self-administered "secret-ballot" questionnairethan when they were interviewed face-to-face. While there weresome suggestive interactions of this mode-of-data collectioneffect with age and sex, and with the partisan atmosphere ofthe precinct in which the interviews were conducted, they wereborderline in significance, inconsistent in pattern, or difficuitto interpret. More important, comparisons with official electionreturns (the truth) indicated that the secret-ballot techniquewas more accurate than were face-to-face interviews in estimatingthe final outcome on the most socially sensitive of three self-reportedvotes: a vote for or against a tax levy for elderly services.Using a genuine secret ballot in the tradition of the olderGallup preelection polls can thus increase the validity of self-reportsin exit polls today.  相似文献   
997.
Implementing partial least squares   总被引:2,自引:0,他引:2  
Partial least squares (PLS) regression has been proposed as an alternative regression technique to more traditional approaches such as principal components regression and ridge regression. A number of algorithms have appeared in the literature which have been shown to be equivalent. Someone wishing to implement PLS regression in a programming language or within a statistical package must choose which algorithm to use. We investigate the implementation of univariate PLS algorithms within FORTRAN and the Matlab (1993) and Splus (1992) environments, comparing theoretical measures of execution speed based on flop counts with their observed execution times. We also comment on the ease with which the algorithms may be implemented in the different environments. Finally, we investigate the merits of using the orthogonal invariance of PLS regression to improve the algorithms.  相似文献   
998.
The standard approach to non-parametric bivariate density estimation is to use a kernel density estimator. Practical performance of this estimator is hindered by the fact that the estimator is not adaptive (in the sense that the level of smoothing is not sensitive to local properties of the density). In this paper a simple, automatic and adaptive bivariate density estimator is proposed based on the estimation of marginal and conditional densities. Asymptotic properties of the estimator are examined, and guidance to practical application of the method is given. Application to two examples illustrates the usefulness of the estimator as an exploratory tool, particularly in situations where the local behaviour of the density varies widely. The proposed estimator is also appropriate for use as a pilot estimate for an adaptive kernel estimate, since it is relatively inexpensive to calculate.  相似文献   
999.
Applied sociology is basically what sociologists do for nonsociologists and sometimes for themselves. Applied sociology includes the teaching of sociology as one of the liberating arts and sciences. It also involves the practice of sociology outside academia in the public and private sectors. Either way, applied sociology needs support groups, and state sociological associations need useful things to do beyond their traditional interests in academic teaching and research. Professional sociological associations, and especially those that serve at the local, state level, can become important support groups for applied sociology. This article suggests five types of applied sociology projects appropriate for state associations. These are volunteering applied sociology; doing applied sociology through consulting; making the value of sociological applications more visible; identifying applied sociology jobs for our baccalaureate, master's, and doctoral graduates; and helping to improve the socioeconomic outlook for our academic colleagues and, in turn, ourselves. State associations provide an organizational base, proximate members, and local opportunities for applying sociology. Ron Wimberley, teaches sociological research methods and does research on the southern Black Belt and other topics. He also attempts applied sociology through volunteer work, consulting, and occasional leaves from his university position. Catherine Harris of Wake Forest University is appreciated for suggesting the topic. The author is responsible for the views expressed in the article.  相似文献   
1000.
The history of sociology is marked by periods of theoretical pluralism and hegemony. Their interplay has resulted in the slow and uneven development of the discipline. Today, however, bodies of theory and practice have become so diverse that many scholars worry that sociology is in a state of disintegration. The theoretical career of Talcott Parsons provides a microcosm in which to explore similar processes. Building on the success of The Structure of Social Action, Parsons led a movement that transformed Harvard's Department of Sociolgy into the Department of Social Relations. There he attempted a grander, but failed synthesis in Toward A General Theory of Action. His case provides a situation in which to explore features of disciplinary integration and fragmentation. The comparison stimulates one to fashion an informed sense of whether sociology is now facing its latest crisis or may be in the process of decomposition as a corpus of study. This research was supported by grants from the American Sociological Association's Fund for the Advancement of the Discipline and by Indiana University Northwest through a sabbatical leave.  相似文献   
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