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201.
My aim was to study the experiences and priorities of two age groups of social work students practicing in client-centered social work. This article is based on the research on rationality and language games in social work. The target groups of the research project as a whole were the actors: the heads and social workers or activists in public social welfare and health care agencies and institutions and in voluntary associations and action groups, and finally, two subsequent classes of students from a school of social work, during their practicing periods. This article concentrates on the trainees. At first, the trainees wrote essays and kept diaries. Secondly, they marked their standings on graphs visualizing different types of information contents and social relation structures. Thirdly, they made their choices of reasons for and solutions to social problems on a problem wheel. The trainees' study, using different data gathering techniques, partly confirms the results of the research of the other actor groups, in which the data were derived using questionnaires and interviews. The trainees' study shows variation in the respondents' priorities within and between specified social problem categories. Qualitatively analyzed, however, the characterizations of social work, both those who currently act in and those aiming to enter this field, resemble one another.  相似文献   
202.
INNUMERACY ABOUT MINORITY POPULATIONS   总被引:1,自引:0,他引:1  
We use a small but nationally representative sample to investigatethe sources of innumeracy regarding the proportion of blacks,Hispanics, and Jews in the U.S. population. In addition to anumber of standard demographic differences, we find that overestimatesare closely related to region as well as to the density of thelocal black/Hispanic population. The extent to which minoritypopulations are perceived as a kind of threat is also relatedto perceived proportions, though the direction of causalitycannot be determined. We discuss the meaningfulness of thesepopulation estimates and speculate on whether trying to improvethem would alter attitudes toward minorities.  相似文献   
203.
Recent studies demonstrating a concentration dependence of elimination of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) suggest that previous estimates of exposure for occupationally exposed cohorts may have underestimated actual exposure, resulting in a potential overestimate of the carcinogenic potency of TCDD in humans based on the mortality data for these cohorts. Using a database on U.S. chemical manufacturing workers potentially exposed to TCDD compiled by the National Institute for Occupational Safety and Health (NIOSH), we evaluated the impact of using a concentration- and age-dependent elimination model (CADM) (Aylward et al., 2005) on estimates of serum lipid area under the curve (AUC) for the NIOSH cohort. These data were used previously by Steenland et al. (2001) in combination with a first-order elimination model with an 8.7-year half-life to estimate cumulative serum lipid concentration (equivalent to AUC) for these workers for use in cancer dose-response assessment. Serum lipid TCDD measurements taken in 1988 for a subset of the cohort were combined with the NIOSH job exposure matrix and work histories to estimate dose rates per unit of exposure score. We evaluated the effect of choices in regression model (regression on untransformed vs. ln-transformed data and inclusion of a nonzero regression intercept) as well as the impact of choices of elimination models and parameters on estimated AUCs for the cohort. Central estimates for dose rate parameters derived from the serum-sampled subcohort were applied with the elimination models to time-specific exposure scores for the entire cohort to generate AUC estimates for all cohort members. Use of the CADM resulted in improved model fits to the serum sampling data compared to the first-order models. Dose rates varied by a factor of 50 among different combinations of elimination model, parameter sets, and regression models. Use of a CADM results in increases of up to five-fold in AUC estimates for the more highly exposed members of the cohort compared to estimates obtained using the first-order model with 8.7-year half-life. This degree of variation in the AUC estimates for this cohort would affect substantially the cancer potency estimates derived from the mortality data from this cohort. Such variability and uncertainty in the reconstructed serum lipid AUC estimates for this cohort, depending on elimination model, parameter set, and regression model, have not been described previously and are critical components in evaluating the dose-response data from the occupationally exposed populations.  相似文献   
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206.
In this paper, the task of determining expected values of sample moments, where the sample members have been selected based on noisy information, is considered. This task is a recurring problem in the theory of evolution strategies. Exact expressions for expected values of sums of products of concomitants of selected order statistics are derived. Then, using Edgeworth and Cornish-Fisher approximations, explicit results that depend on coefficients that can be determined numerically are obtained. While the results are exact only for normal populations, it is shown experimentally that including skewness and kurtosis in the calculations can yield greatly improved results for other distributions.  相似文献   
207.
Are children as young as 2 years old able to interact in groups of three? The study applied the family triad model first introduced by Parke, Power, and Gottman (1979 ) to the case of peer interaction. In Experiment 1 , the model was refined for use in studies of peer interaction and applied to an existing dataset of 16 triads of newly acquainted 24‐month‐olds. In Experiment 2 , the triadic coding system was further refined and applied to 12 single‐sex triads of newly acquainted 2‐year‐olds. The findings demonstrated that 2‐year‐olds are capable of triadic interaction although the predominant interaction pattern in triads is still dyadic. Contrary to past reports, triadic interaction was more likely to occur when the children were not in conflict. Both girls and boys were capable of triadic interaction.  相似文献   
208.
The limitations and errors in data sources, primarily censuses and vital statistics, concerning mortality in Chile from 1865 to 1940 are examined. Solutions are offered to adjust the sources' underestimations, particularly with regard to infant mortality.  相似文献   
209.
The Immigration Reform and Control Act (IRCA) of 1986 made 4 types of aliens eligible to receive legalization benefits: 1) those who resided "continuously" in the US since January 1, 1982; 2) those who had worked in the US perishable-crop agriculture for 90 "man-days" in specified time periods (Special Agricultural Workers [SAWS]); 3) those who were in the US since before January 1, 1972; and 4) those classified as Cuban/Haitian entrants and who had been in the US since January 1, 1982. Estimates of the number of aliens eligible for legalization, not including SAWS, ranges from 1.834 million to 2.56 million. Estimates of undercounts of undocumented aliens are 10% for those who entered before 1975 and 37.5% for those who arrived after 1975. Other refinements in the estimates of undocumented aliens include adjustments for 1) ethnic group and location, 2) the growth of the undocumented population between the census date and the legalization eligibility date under IRCA, and 3) emigration and deportation rates. Out of the 1,581,800 applicants entered into the Immigration and Naturalization Service (INS) computers (from a total of 2.15 million applicants) as of May 20, 1988, 73.7% were Mexican nationals. Only 5 other countries contributed more than 1%: El Salvador (6.5%), Haiti (2.3%), Guatemala (2.2%), the Philippines (1%), and Colombia (1%). The Mexican percentage was unexpectedly high, perhaps because the legalization had been much more successful in the Southwest than anywhere else in the country. Reasons that Mexicans have a higher legalization participation rate than other nationalities include 1) the distant eligibility date; 2) ethnic differences among non-Mexican nationalities; 3) particularly in the northeast, fears of exposing one's illegal status to INS; 4) the difficulty of information reaching ethnic communities, 5) the reluctance of those already undergoing the naturalization process to risk the legalization process; and 6) the reluctance of employees to admit employment of undocumented aliens. In the end, more than 90% of applicants are expected to be granted temporary resident alien status (and about 70% of agricultural workers), for a total of more than 2 million people. Researchers estimate that 2.5 - 3 million more persons remain in an undocumented status in the US.  相似文献   
210.
The authors develop an econometric model to examine the impact of migration on fertility in Greece in the period 1968-1986. In the model, the fertility equation is considered within a simultaneous equation system, and international migration is included as an explanatory factor of both fertility and per capita income. (SUMMARY IN FRE AND SPA)  相似文献   
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