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991.
Evaluations of the impact of social programs are often carried out in multiple sites, such as school districts, housing authorities, local TANF offices, or One‐Stop Career Centers. Most evaluations select sites purposively following a process that is nonrandom. Unfortunately, purposive site selection can produce a sample of sites that is not representative of the population of interest for the program. In this paper, we propose a conceptual model of purposive site selection. We begin with the proposition that a purposive sample of sites can usefully be conceptualized as a random sample of sites from some well‐defined population, for which the sampling probabilities are unknown and vary across sites. This proposition allows us to derive a formal, yet intuitive, mathematical expression for the bias in the pooled impact estimate when sites are selected purposively. This formula helps us to better understand the consequences of selecting sites purposively, and the factors that contribute to the bias. Additional research is needed to obtain evidence on how large the bias tends to be in actual studies that select sites purposively, and to develop methods to increase the external validity of these studies. © 2012 by the Association for Public Policy Analysis and Management.  相似文献   
992.
Intra-alveolar hemorrhage and hemosiderin have been cited as possible markers of recent and remote asphyxial events. Little study has been undertaken of the potential significance of intra-alveolar hemosiderin in adults as a potential marker of previous sublethal asphyxial episodes. Ten cases of lethal sexual asphyxia (an entity known to be associated with repetitive sublethal asphyxial episodes) and 20 randomly selected, age- and sex-matched controls had sections of lung stained for hemosiderin. Subsequently, intra-alveolar, iron-containing macrophages were counted. All cases were men (ages 15-50 years; mean 31.8). No significant increase in hemosiderin was found in victims of sexual asphyxia, indicating that asphyxial episodes in sublethal sexual asphyxial activities may not be sufficiently intense or prolonged to cause intra-alveolar hemorrhage or that intra-alveolar hemorrhage in adults is a relatively nonspecific finding. These results do not support intra-alveolar hemosiderin deposition as a marker for previous sublethal asphyxial events in autoerotic asphyxia.  相似文献   
993.
994.
An acoustic-phonetic forensic-voice-comparison system was constructed using the time-averaged formant values of tokens of 61 male Chinese speakers' /i/, /e/, and /a/ monophthongs as input. Likelihood ratios were calculated using a multivariate kernel density formula. A separate set of likelihood ratios was calculated for each vowel phoneme, and these were then fused and calibrated using linear logistic regression. The system was tested via cross-validation. The validity and reliability of the results were assessed using the log-likelihood-ratio-cost function (C(llr), a measure of accuracy) and an empirical estimate of the credible interval for the likelihood ratios from different-speaker comparisons (a measure of precision). The credible interval was calculated on the basis of two independent pairs of samples for each different-speaker comparison pair.  相似文献   
995.
We tested the hypothesis that beliefs in the purported attributes of recovered memories of child sexual abuse (CSA) are associated with knowledge of the "recovered/false memory debate", and that such beliefs will be related to assessments of the credibility of statements made by participants in a vignette about CSA. Participants from five countries (the United States, Canada, New Zealand, the United Kingdom and Israel) responded to a questionnaire regarding beliefs about recovered memory as well as self-reported exposure to and knowledge of the debate. In addition, they assessed the credibility of statements made by a daughter (reporting recovery of memories of sexual abuse by her father), her father (denying the allegation and accusing the daughter's therapist of implanting in her false "memories" of abuse), and two experts (each supporting one of the two protagonists). We found that prior knowledge of the debate across countries was linked to beliefs in specific attributes of recovered memories and to a subset of the credibility assessments of statements made by the protagonists and their experts. For individuals, however, credibility assessments were unrelated to knowledge of the debate, but they were related to beliefs about memory recovery. Finally, credibility of the protagonists' statements was differentially associated with those made by the daughter's and the father's experts. The results suggest that whereas familiarity with the debate does not affect the credibility of the statements made by the complainant and the accused, expert testimony does, as has been found in prior research. The psycholegal implications of this conclusion are discussed.  相似文献   
996.
The article describes characteristics of pregnant women presenting to the Emergency Department (ED) who are experiencing current violence and presented a screening tool to identify pregnant women experiencing violence. Women completed an in-person interview regarding violence, sociodemo-graphic factors, health status, and drug use. Fifteen percent of women reported at least one episode of violence during the pregnancy. Young age (OR = 3.37, 95% CI: 1.79-6.36), current alcohol use (OR = 1.53, 95% CI: 1.06-2.19), current marijuana use (OR = 1.96, 95% CI: 1.32-2.92), less than a high school education (OR = 1.46, 95% CI: 1.01-2.12), and a prior diagnosis of trichomonas (OR = 1.81, 95% CI: 1.20-2.72) were significantly related to experiencing current violence. Screening patients using these five characteristics identified 8 out of 10 women reporting violence (sensitivity = 75.6%). These results identify a set of predictors that may be helpful in identifying pregnant women who are experiencing current domestic violence.  相似文献   
997.
Prior event-based research regarding the relationship between alcohol and violence suffers from important limitations, including the absence of a comparison group, an inappropriate comparison group, or a comparison group that could be considered appropriate but does not control for potential confounders. To overcome such limitations, we use a matched pair design. Drawing on interviews with men imprisoned for an aggravated assault or homicide committed in response to a conflict with another man, we examine matched pairs of violent and nonviolent conflicts nested within respondents. The results suggest that guns mediate the relationship between alcohol and lethal male-male violence.  相似文献   
998.
999.
Churches serve vital roles in African American communities, where disease burden is disproportionately greater and healthcare access is more limited. Although church leadership often must approve programs and activities conducted within churches, little is known about their perception of churches as health promotion organizations, or the impact of church-based health promotion on their own health. This exploratory study assessed perceptions of church capacity to promote health among 27 rural, African American clergy leaders and report the relationship between their own health and that of their congregation. Results indicate a perceived need to increase the capacity of their churches to promote health. Most common were conducting health programs, displaying health information, kitchen committee working with the health ministry, partnerships outside of the church, and funding. Findings lay the foundation for the development of future studies of key factors associated with organizational change and health promotion in these rural church settings.  相似文献   
1000.
This Article analogizes early semiconductor technology and its surrounding economics with isolated genes, stem cells, and related bioproducts, and their surrounding economics, to make the case for sui generis (of its own class) intellectual property protection for isolated bioproducts. Just as early semiconductors failed to meet the patent social bargain requiring novelty and non-obviousness in the 1980s, isolated genes and stem cells currently fail to meet the patent bargain requirements of non-obviousness and eligible subject matter that entitle them to traditional intellectual property protection. Like early semiconductor chip designs, nevertheless, the high cost of upstream bioproduct research and development, coupled with the need to sustain continued economic growth of the biotechnology industry, mandates that Congress provide some level of exclusive rights to ensure continued funding for this research. Sui generis intellectual property protection for isolated bioproducts would preserve the incentive to continue innovation in the field. As illustrated by the semiconductor industry, however, such sui generis protection for this technology must include limitations that address the need to provide an appropriate level of public access to facilitate downstream product development and enrich the public domain.  相似文献   
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