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91.
92.
The contemporary retreat from marriage in the United States has had a differential impact across socioeconomic and racial groups. Here, 1990 marriage rates and propensities for Virginia, North Carolina, and Wisconsin are analyzed regarding (a) the likelihood that persons in different groups ever marry and (b) patterns of partner choice with respect to race and educational level. Marriage remains strong in most race‐education groups but is substantially lower among Blacks and among those with less than 12 years of education. Patterns of partner choice have shifted to show greater symmetry between the educational levels of brides and grooms. Changes have been modest with regard to the level and pattern of interracial (Black‐White) marriage. Marriage is increasingly a union of equals, but a union chosen more by Whites than by Blacks and more by the well educated than by the poorly educated.  相似文献   
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95.
We compare the patterns of household division of labor in Germany and Israel—two countries that share key elements of the corporatist welfare regime but differ in their gender regimes—and evaluate several hypotheses using data from the 2002 International Social Survey Program. Although time constraints and relative resources affect the division of household labor and women’s housework in both societies, we find that in Germany the gender order of household labor is more rigid, whereas in Israel the spouses’ linked labor market status exerts distinctive effects. We also find significant relationships between gender ideology and the division of household labor. We discuss the theoretical advantages of approaching the comparative study of gender inequality from the vantage point of family and gender regimes.  相似文献   
96.
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   
97.
Planning the gambling environment requires protection of the public's health, safety and welfare. Whereas most public gaming provisions and statutes address the public's fears of organized crime as well as some welfare needs, rarely do they safeguard the public's health regarding the spread of the mental disease known as pathological gambling. Measurement of the prevalence and incidence of this disease would enable policy planners to evaluate both the state's responsibility for an epidemic and the adequacy of publicly funded treatment programs. The purpose of this paper is to examine the methods which underlie three different estimates of the prevalence rate of pathological gambling and to critique them in the light of sound epidemiological procedure. In 1975, the Institute for Social Research (ISR) of the University of Michigan conducted a national survey and a survey of the state of Nevada on behalf of the U.S. Commission on a National Policy Toward Gambling. Using discriminant function analysis coupled with subjective inspection of cases in the at-risk pool, the researchers estimated rates of probable and potential pathological gamblers. In 1984 and 1985, this author surveyed residents in the Delaware Valley and the state of Ohio using the cumulative clinical signs method which also posited rates of probable and potential pathological gamblers. In 1986, researchers at the Office of Mental Health for the State of New York employed a formal screening device to survey residents and proposed a rate of probable pathological gamblers and a rate of problem — although not pathological — gamblers. All three approaches produced different estimates. The utility of prevalence and incidence rate research in this field is threatened by a lack of consensus about the proper epidemiological procedure to be employed in arriving at these estimates. There is also confusion about the distinction between a probable and a potential pathological gambler. The planning purpose, method, validity and reliability of prevalence rate research about pathological gambling are addressed in this paper.  相似文献   
98.
Principal curves revisited   总被引:15,自引:0,他引:15  
A principal curve (Hastie and Stuetzle, 1989) is a smooth curve passing through the middle of a distribution or data cloud, and is a generalization of linear principal components. We give an alternative definition of a principal curve, based on a mixture model. Estimation is carried out through an EM algorithm. Some comparisons are made to the Hastie-Stuetzle definition.  相似文献   
99.
Book reviews     
Nathan Glazer Ethnic Dilemmas Harvard, Harvard University Press. 1985

Giddens, Anthony The Constitution of Society, Berkeley, University of California, 1985, pp.XXXVII, 402. Notes, glossary, diagrams, bibliographic notes and index.

Jeremy Rifkin Declaration of a Heretic. Boston. London, Melbourne and Henley, Routledge and Kegan Paul, 1985, pp.X,140.

Ted Benton The Rise and Fall of Structural Marxism: Althusser and his Influence, New York, St.Martin's Press, 1984, pp. VII,259.

Raymond L. Garthoff Détente and Confrontation Washington, The Brookings Institution, 1985, pp.XVI,1126.

Joseph J. Collins The Soviet Invasion of Afghanistan. A Study in the Use of Force in Soviet Foreign Policy, Massachusetts/Toronto, D.C. Heath and Company/Lexington, 1986, pp. XV, 195.

Jan Shipps Mormonism: The Story of a New Religious Tradition, Chicago, University of Illinois Press, 1985, pp.211.

Robert Jay Lifton Home from the War: Vietnam Veterans: Neither Victims nor Executioners, New York, Basic Books, 1985, pp.478  相似文献   

100.
This paper examines the mediating mechanism of the relationship between institutional voids (IVs) and inter‐firm cooperation and the moderating role of economic adversity in the context of small and medium‐sized enterprises (SMEs) based in emerging markets. The hypotheses are tested using time‐lagged survey data from 214 SMEs in Ghana. The findings provide support for the hypotheses by showing that: (1) IVs positively influence the use of government research and development (R&D) support; (2) the use of government R&D support mediates the relationship between IVs and inter‐firm cooperation; and (3) economic adversity positively moderates the relationship between IVs and the use of government R&D support. The findings contribute to understanding the role of IVs in inter‐firm cooperation. The wider implications for theory and practice are examined.  相似文献   
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