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951.
952.
As STD infections including HIV increase in the United States, it has become increasingly important to policy makers to ascertain the extent to which knowledge and perceptions of AIDS risk affect an individual's probability of altering their sexual or contraceptive behavior to avoid infection. This paper examines the extent to which women's perceptions of their own and their partners' risk of HIV infection affects the probability of using a condom for protection against sexually transmitted diseases. This paper also examines the extent to which HIV testing may affect motivation for condom use. Crosstabulations reveal that prophylactic condom use is more prevalent among women who have been tested for HIV and increase as perceptions of their chance (and their partner's chance) of being positive increases. The multivariate results from this study indicate that having an HIV test significantly predicts the likelihood of using a condom for STD prevention for US women. Furthermore, women who perceive themselves to be at least somewhat likely to be HIV positive have a higher probability of using a condom to prevent sexually transmitted disease, and women who perceive their partners to be HIV positive are twice as likely as other women to use a condom for STD prevention. However, women who consider themselves likely to be HIV positive are no more likely to use a condom than those who consider themselves not at risk. 相似文献
953.
954.
Scientific techniques for inventory management typically are applied to systems containing many items. Such techniques require an estimation of the demand variance (and mean) of each item from historical data. This research demonstrates a significant potential for improvement in system cost performance from using least-squares regression fits of a variance-to-mean functional relation instead of the standard statistical variance estimate. Even when there is a moderate degree of heterogeneity among items and when the form of the variance-to-mean relation is misspecified, substantial cost savings may be realized. The cost of statistical uncertainty may be reduced by half. The research also provides evidence that system cost is fairly insensitive to the number of items used to fit the regression. This paper provides the underlying reason why a regression-derived variance estimator yields lower cost: it is less variable than the usual individual item variance estimator. 相似文献
955.
In a recent paper, Pinto and Mabert [5] presented a lot-sizing rule and an improvement procedure for the joint lot-sizing problem with zero setup costs. We show that this procedure often yields infeasible schedules. We also present and discuss two interesting properties of the joint lot-sizing problem with zero setup costs. A numerical example to illustrate the second property is provided. 相似文献
956.
Philip A. Cowan Carolyn Pape Cowan Marsha Kline Pruett Kyle Pruett Jessie J. Wong 《Journal of marriage and the family》2009,71(3):663-679
Few programs to enhance fathers' engagement with children have been systematically evaluated, especially for low‐income minority populations. In this study, 289 couples from primarily low‐income Mexican American and European American families were randomly assigned to one of three conditions and followed for 18 months: 16‐week groups for fathers, 16‐week groups for couples, or a 1‐time informational meeting. Compared with families in the low‐dose comparison condition, intervention families showed positive effects on fathers' engagement with their children, couple relationship quality, and children's problem behaviors. Participants in couples' groups showed more consistent, longer term positive effects than those in fathers‐only groups. Intervention effects were similar across family structures, income levels, and ethnicities. Implications of the results for current family policy debates are discussed. 相似文献
957.
According to standard theory founded on Harsanyi (J Polit Econ 61:434–435, 1953; 63:309–321, 1955) a social welfare function can be appropriately based on the individual’s approach to choice under uncertainty. We investigate how people really do rank distributions in terms of welfare. According to Harsanyi, the evaluation can be done from the standpoint of an uninvolved external judge, a public official, for example, or by a person who knows that she holds one of the positions in society, with an equal chance for any of the available positions. Are these two structures to be viewed differently? We use a questionnaire experiment to focus on the two different interpretations of the Harsanyi approach. There are important, systematic differences that transcend the cultural background of respondents. 相似文献
958.
The present research examined whether the emotions of others (i.e., disappointment versus happiness with respect to a received outcome) influence own self-esteem when being overpaid. Results from two experiments demonstrated that participants reported higher performance self-esteem when the other expressed happiness rather than disappointment. This effect was only found in the condition where one was overpaid relative to the condition where one did not yet know one’s own outcome. In the second experimental study we further found that this interaction between the emotion of the other and the distribution situation only emerged among participants low (relative to high) in personal need for structure. Implications with respect to the relationship between overpayment and self-esteem and the interpersonal effects of emotions in this process are discussed. 相似文献
959.
As approaches to positive youth development (PYD) gain momentum, the issue of sexuality – a critical component of human development – is being subsumed by ideological debates. In the current political climate, sexuality education is often relegated to biological and/or values-based approaches, neglecting essential relational and collective aspects of sexuality. Through the explication of sexuality as an important component of youth's social ecology, this paper provides a conceptual link between the goals of the Sexuality Information and Education Council of the United States' (SIECUS) Guidelines for comprehensive sexuality education and those of PYD. We argue that sexuality, as a normative part of human development, culture, identity, and relationships, be approached from an asset-based perspective, rather than a deficit-based perspective. We propose a framework that illustrates how aspects of sexuality are embedded within PYD contexts, and demonstrates how a sexuality education program rooted in SIECUS guidelines can further PYD goals across community contexts. 相似文献
960.
Chandrika Ismail A De Alwis Seneviratne R Newcombe PA Wanigaratne S 《Evaluation review》2009,33(1):83-97
This study translated and validated the Substance Use Risk Profile Scale (SURPS) among 13 to 18 year old Sri Lankan adolescents attending school. A standard systematic translation procedure was followed to translate the original SURPS into Sinhala language. A Delphi process was conducted to determine judgmental validity of Sinhala SURPS. Confirmatory factor analysis was performed to test the translated version against the original theoretical model of the SURPS. Test-retest and internal consistency were used to ensure reliability. A few terms in one of the items posed some difficulty in translating into Sinhala. Adequate judgmental validity was determined except for one item, which was modified to suit the Sri Lankan setting. The four subscales introversion/ hopelessness, impulsivity, sensation seeking and anxiety sensitivity showed satisfactory test-retest reliability estimates of .74, .68, .76, and .88, respectively. The Sinhala SURPS is applicable in Sri Lankan context. Several implications based on the results are discussed. 相似文献