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Repeated cross‐sectional (RCS) designs are distinguishable from true panels and pooled cross‐sectional time series (PCSTS) since cross‐sectional units (e.g., individual survey respondents) appear but once in the data. This poses two serious challenges. First, as with PCSTS, autocorrelation threatens inferences. However, common solutions like differencing and using a lagged dependent variable are not possible with RCS since lags for i cannot be used. Second, although RCS designs contain information that allows both aggregate‐ and individual‐level analyses, available methods—from pooled ordinary least squares to PCSTS to time series—force researchers to choose one level of analysis. The PCSTS tool kit does not provide an appropriate solution, and we offer one here: double filtering with ARFIMA methods to account for autocorrelation in longer RCS followed by the use of multilevel modeling to estimate both aggregate‐ and individual‐level parameters simultaneously. We use Monte Carlo experiments and three applied examples to explore the advantages of our framework. 相似文献
845.
Parent and Metabolite Opioid Drug Concentrations in Unintentional Deaths Involving Opioid and Benzodiazepine Combinations,,
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Marcia D. Fields Pharm.D. Marie A. Abate B.S. Pharm.D. Lan Hu B.S.N. D. Leann Long Ph.D. Matthew L. Blommel Pharm.D. Nabila A. Haikal M.D. James C. Kraner Ph.D. 《Journal of forensic sciences》2015,60(4):950-956
Effects of benzodiazepines on postmortem opioid parent and parent/metabolite blood concentration ratios were determined for fentanyl‐, hydrocodone‐, methadone‐, or oxycodone‐related accidental deaths. These opioids are partially metabolized by the CYP3A4 enzyme system, which is also affected by diazepam and alprazolam. Opioid/metabolite combinations examined were as follows: fentanyl/norfentanyl, hydrocodone/dihydrocodeine, methadone/EDDP, and oxycodone/oxymorphone. Parent opioid concentrations were analyzed for 877 deaths. Parent/metabolite concentration ratios were analyzed for 349 deaths, excluding cases with co‐intoxicants present known to interfere with opioid elimination. Alprazolam in combination with diazepam significantly decreased median hydrocodone concentrations by 48% (p = 0.01) compared to hydrocodone alone. The methadone parent/metabolite concentration ratio was reduced by 35% in the presence of diazepam compared to methadone alone (p = 0.03). Benzodiazepines did not statistically significantly affect fentanyl or oxycodone concentrations. Possible factors affecting opioid concentrations and possible toxicity development, including any differential effects on specific opioids, should continue to be explored. 相似文献
846.
Matthew Watson 《Global Society》2006,20(4):435-451
Fair trade requires that developed country consumers engage in market-based transactions with developing country producers. Yet this is not market trade in any straightforward sense, because the purchase of fairly traded products brings consumers into two market relationships at the same time. One is the market relationship through which consumers buy the product itself, which enables them to act altruistically by consciously paying the price premium that the producer receives. The other is the market relationship through which consumers buy the socially reputable knowledge of having helped a distant stranger, which enables them to harness their ostensibly ethical consumption to a knowingly self-interested action. This latter relationship adds a new dimension to orthodox commodity fetishism. A Polanyian perspective is developed to investigate the way in which fair trade reworks the commodity fetish. This serves as a prelude to an extended discussion of the moral status of the behavioural motivations that underpin fair trade consumption. 相似文献
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848.
Contemporary research on criminal sentencing has analyzed sentencing under numerous sentencing policies, yet the effect of
sentencing policy on outcomes and disparity is not known. A variety of sentencing guidelines systems, one of the more common
sentencing policies, exists throughout the country. In addition, recent Supreme Court decisions regarding sentencing guidelines
are likely to produce alterations to several state sentencing policies over the next few years. Using data from the state
of Florida, the current study examines the effects of policy transformation on sentencing disparity within the focal concerns
of sentencing perspective. The authors view sentencing guidelines as a practical constraint on sentencing decisions that influence
other key variables. The results indicate that sentencing policy transformation has an important effect on both sentencing
decisions and on the factors that shape those decisions. The findings suggest that future sentencing research and theoretical
development would benefit from incorporating measures of policy differences in its analyses. 相似文献
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850.
This article is an examination of the issue of whether the age of electoral majority should be lowered to sixteen. We consider and reject several arguments raised by both sides of the voting age debate. The key issue, we claim, is the political maturity of young people. Drawing on empirical data collected in nationally representative surveys, we argue that the weight of such evidence suggests that young people are, to a significant degree, politically less mature than older people, and that the voting age should not be lowered to sixteen. 相似文献