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981.
Abstract Data from the 1990 U. S. Census are used to examine nonmetro-metro distinctions in the outmarriage patterns of the nation's two largest minority groups—African Americans and Mexican Americans. The analysis is guided by a multilevel model combining individual- and community-level determinants of outmarriage. Consistent with notions suggesting that persons in metro areas are less traditional and, perhaps, more tolerant of those different from them, we find that African Americans living in metro areas are more likely to be married to someone from another racial/ethnic group than their peers in nonmetro areas, even after residential differences in individual and community characteristics are taken into account. On the other hand, controlling for other factors, Mexican Americans living in metro areas are not any more likely than those living in nonmetro settings to be exogamous. One possible explanation for this divergent pattern is the relatively recent urbanization of the Mexican American population. 相似文献
982.
983.
Susan J. Spieker Nancy C. Larson Steven M. Lewis Rachelle D. White Lewayne Gilchrist 《Child and Adolescent Social Work Journal》1997,14(5):335-364
The cognitive and behavioral status at age six years of 185 children of adolescent mothers (60.5% boys) were assessed using the mother (CBCL) and teacher (TRF) report forms of the Child Behavior Checklist and the Bracken Basic Concepts Scale. There was evidence for impairment in all areas of functioning. More than half of the sample exceeded the borderline clinical cutoff (T = 60) on either the CBCL or TRF Total Problem score, and nearly half the sample had Bracken scores that were more than 1 SD below the normative mean. Only 26.9% of the children were in the normal range on all three measures. These results are discussed in terms of implications for social work practice with children and adolescent mother families. 相似文献
984.
Testosterone, Smiling, and Facial Appearance 总被引:1,自引:0,他引:1
James M. Dabbs Jr. 《Journal of Nonverbal Behavior》1997,21(1):45-55
In a study of possible links between testosterone and dominance, 119 men and 114 women provided saliva samples for testosterone assay and posed smiling and not smiling for portrait photographs. Expert judges viewing the photographs found smaller smiles among high than low testosterone men, with less zygomatic major (raising the corners of the mouth) and orbicularis oculi (raising the cheeks and crinkling around the corners of the eyes) muscle activity. Naive judges viewing individual photographs gave higher potency ratings to smiling high testosterone men than smiling low testosterone men. Naive judges viewing photographs grouped into high and low testosterone sets gave higher potency and lower goodness ratings to high than to low testosterone men, regardless of whether they were smiling. Among women, judges found only slight relationships between testosterone and facial appearance. The pattern among men of less smiling with higher testosterone levels fits with research linking testosterone to face-to-face dominance. 相似文献
985.
Audrey Block G. Nicholas Braucht Richard Crispino Robert E. Drake Susan M. Essock Richard Hough Michael W. Kirby Claudia Krueger Jon Nachison Marjorie Robertson Stanley Sacks Graham Staines 《Journal of Social Distress and the Homeless》1997,6(4):261-274
The Collaborative Demonstration Program for Homeless Individuals is providing an opportunity for several community agencies in the United States to explore innovative intervention and treatment strategies to address the needs of homeless people with co-occurring (mental illness and substance abuse) disorders. This cooperative agreement, funded jointly by the Center for Mental Health Services (CMHS) and the Center for Substance Abuse Treatment (CSAT), is a $3 million project supporting programs in various community agencies to develop, document, and evaluate programs for persons who are homeless with co-occurring disorders to be used as models in other communities. The program models include: Assertive Community Treatment, Psychosocial Rehabilitation, Therapeutic Community, and an integrated treatment model. The first phase of the two-phase project funded 16 programs in the U.S. to develop manuals within their primary treatment modalities for homeless people with co-occurring disorders. For Phase II of the project, six of the 16 model programs were competitively selected to demonstrate program impact through formal program evaluation efforts. The data derived from the various projects will be compiled into a compendium of information for state agencies and community service providers throughout the U.S. 相似文献
986.
SUMMARY An optimization problem which provides a new characterization for ridge regression is discussed. A variant of this optimization problem leads to a new family of biased estimators that includes the Stein estimation method and principal components regression as particular cases. The whole approach is illustrated on the basis of real data sets. 相似文献
987.
OLLE HGGSTR
M 《Scandinavian Journal of Statistics》2007,34(4):768-780
Abstract. By means of a series of examples, from classic contributions to probability theory as well as the author's own, an attempt is made to convince the reader that problem solving is often a matter of cooking up an appropriate Markov chain. Topics touched upon along the way include coupling, correlation inequalities, and percolation. 相似文献
988.
MONTSERRAT GUILLEN JENS P. NIELSEN ANA M. PEREZ-MARIN 《Scandinavian Journal of Statistics》2007,34(2):419-431
Abstract. The Nelson–Aalen estimator is well known to be an asymptotically efficient estimator of the cumulative hazard function, see Andersen et al. ( Statistical models based on counting processes , Springer-Verlag, New York, 1993) among many others. In this paper, we show that the efficiency of the Nelson–Aalen estimator can be considerably improved by using more information in the estimation process than the traditional Nelson–Aalen estimator uses. While our approach results in a biased estimator, the variance improvement is substantial. By optimizing the balance between the bias loss and the variance improvement, we obtain results on the efficiency gain. Several examples for known failure time distributions are used to illustrate these ideas. 相似文献
989.
Absenteeism, turnover and disability, and relationships between them have been studied among city bus drivers in the Netherlands. The theoretical framework for the study was a cumulative process model of work and health. Absenteeism among these drivers was two to three times as high as the national average, while the risk of disablement was more than twice as high as the risk for male Dutch civil servants in general. Bus drivers who had to leave their job for medical reasons did so at a younger age than other groups of civil servants. The main conditions leading to disablement related to the back, tendons and joints (35%), mental disorders (35%) and cardiovascular diseases (12%). It was shown that long-term absenteeism is a strong precursor of future disability. The research suggests a work-related process of progressive deterioration of health and well-being over a reasonably long period of time. Driving city buses seems to be an occupation with high risks for health and well-being. 相似文献
990.
Robert M. Bohm 《Sociological inquiry》1990,60(3):285-297
This study attempts to identify stimuli that produce changes in death penalty opinions and to determine whether public commitment to a death penalty opinion has an effect on that opinion. Consistent with previously reported findings, the results of this study suggest that public commitment has a substantial inhibitory effect on opinion change. Reasons for both changing and maintaining death penalty opinions are provided, and the implications of the research are discussed. 相似文献