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461.
The primary objective of a multi-regional clinical trial is to investigate the overall efficacy of the drug across regions and evaluate the possibility of applying the overall trial result to some specific region. A challenge arises when there is not enough regional sample size. We focus on the problem of evaluating applicability of a drug to a specific region of interest under the criterion of preserving a certain proportion of the overall treatment effect in the region. We propose a variant of James-Stein shrinkage estimator in the empirical Bayes context for the region-specific treatment effect. The estimator has the features of accommodating the between-region variation and finiteness correction of bias. We also propose a truncated version of the proposed shrinkage estimator to further protect risk in the presence of extreme value of regional treatment effect. Based on the proposed estimator, we provide the consistency assessment criterion and sample size calculation for the region of interest. Simulations are conducted to demonstrate the performance of the proposed estimators in comparison with some existing methods. A hypothetical example is presented to illustrate the application of the proposed method.  相似文献   
462.
The most extensively studied influence on adolescent conduct problem behaviors is peers, and the literature points to genetics as one source of individual differences in peer influence. The purpose of this study was to test the hypothesis that an environmental sensitivity genetic index comprised of DRD4, 5‐HTTLPR, and GABRA2 variation would moderate the association between peer and adolescent conduct problems. Latent growth modeling was applied to PROSPER project longitudinal data from adolescents and their peers. Results showed the hypothesis was supported; adolescents with more copies of putative sensitivity alleles were more strongly influenced by their peers. The interaction form was consistent with differential susceptibility in follow‐up analyses. Strengths and weaknesses of genetic aggregates for sensitivity research are discussed.  相似文献   
463.
How do young children negotiate conflicts with peers that result in mutually beneficial resolution and peaceful interaction after conflict? A few studies suggest that when children use conciliatory strategies in conflict, socially adaptive outcomes are more likely to be achieved. The present study explores the relative associations of types of children's conciliatory conflict resolution strategies (i.e., prosocial, compliance‐oriented, solution‐oriented, and verbal clarification/apology) with conflict outcomes to contribute to knowledge of the discrete behaviors that might have salience for conflict resolution training. Socially adaptive conflict outcomes were expected to strongly relate to children's resolution strategies of a prosocial nature as well as to teacher or peer interventions encouraging prosocial behavior or empathy. Sampled conflicts (N = 521) were collected through field observations of 107 ethnically/racially and socioeconomically diverse four‐ to seven‐year‐old children. Logistic regression analyses with bootstrap‐based inference suggested that children's prosocial behaviors in conflict were most strongly tied to mutually beneficial resolution and peaceful postconflict interaction, when controlling for relevant covariates. Other conciliatory strategies varied in their association with socially adaptive outcomes. The hypothesis regarding third‐party interventions encouraging prosociability or empathy could not be examined due to infrequent occurrence. Insights for future research on children's socially adaptive conflict negotiations are discussed.  相似文献   
464.
465.
This paper concerns the forecasting of seasonal intraday time series that exhibit repeating intraweek and intraday cycles. A recently proposed exponential smoothing method involves smoothing a different intraday cycle for each distinct type of day of the week. Similar days are allocated identical intraday cycles. A limitation is that the method allows only whole days to be treated as identical. We introduce a new exponential smoothing formulation that allows parts of different days of the week to be treated as identical. The result is a method that involves the smoothing and initialisation of fewer terms. We evaluate forecasting up to a day ahead using two empirical studies. For electricity load data, the new method compares well with a range of alternatives. The second study involves a series of arrivals at a call centre that is open for a shorter duration at the weekends than on weekdays. Among the variety of methods considered, the new method is the only one that can model in a satisfactory way in this situation, where the number of periods on each day of the week is not the same.  相似文献   
466.
This study addressed the role of actual and perceived similarity in peer rejection of socially anxious adolescents. Videotapes of 20 high and 20 low socially anxious adolescents (13–17 years old) giving a speech were rated by groups of unfamiliar peers with regard to perceived similarity and desire for future interaction (lower scores indicating rejection). Actual similarity between speakers and observers regarding social anxiety and gender was also taken into account. Findings showed that high socially anxious students were more rejected and that perceived but not actual similarity between peer observers and speakers (partly) mediated rejection.  相似文献   
467.
The amount of radon in natural gas varies with its source. Little has been published about the radon from shale gas to date, making estimates of its impact on radon‐induced lung cancer speculative. We measured radon in natural gas pipelines carrying gas from the Marcellus Shale in Pennsylvania and West Virginia. Radon concentrations ranged from 1,520 to 2,750 Bq/m3 (41–74 pCi/L), and the throughput‐weighted average was 1,983 Bq/m3 (54 pCi/L). Potential radon exposure due to the use of Marcellus Shale gas for cooking and space heating using vent‐free heaters or gas ranges in northeastern U.S. homes and apartments was assessed. Though the measured radon concentrations are higher than what has been previously reported, it is unlikely that exposure from natural gas cooking would exceed 1.2 Bq/m3 (<1% of the U.S. Environmental Protection Agency's action level). Using worst‐case assumptions, we estimate the excess lifetime (70 years) lung cancer risk associated with cooking to be 1.8×10?4 (interval spanning 95% of simulation results: 8.5×10?5, 3.4×10?4). The risk profile for supplemental heating with unvented gas appliances is similar. Individuals using unvented gas appliances to provide primary heating may face lifetime risks as high as 3.9×10?3. Under current housing stock and gas consumption assumptions, expected levels of residential radon exposure due to unvented combustion of Marcellus Shale natural gas in the Northeast United States do not result in a detectable change in the lung cancer death rates.  相似文献   
468.
This study assesses the degree to which the relationship between the environmental demands of countries (measured as ecological footprint per capita) and well-being (measured as life expectancy) has changed over the last several decades (1961–2007) and whether the nature and extent of these changes differ between developed and less-developed countries. Pooled ordinary least squares regression results indicate that decoupling has occurred among developed countries, where the relationship between ecological footprint and life expectancy weakened substantially over time, becoming negative in later years. In less-developed countries, the relationship has intensified substantially, with the effect of ecological footprint on life expectancy becoming stronger over time. Fixed-effects regression results provide similar results for developed countries but indicate slight decoupling between increases in ecological footprint and life expectancy among less-developed countries. The implications of these results are discussed in the context of contraction and convergence approaches to sustainability.  相似文献   
469.
Complex models can only be realized a limited number of times due to large computational requirements. Methods exist for generating input parameters for model realizations including Monte Carlo simulation (MCS) and Latin hypercube sampling (LHS). Recent algorithms such as maximinLHS seek to maximize the minimum distance between model inputs in the multivariate space. A novel extension of Latin hypercube sampling (LHSMDU) for multivariate models is developed here that increases the multidimensional uniformity of the input parameters through sequential realization elimination. Correlations are considered in the LHSMDU sampling matrix using a Cholesky decomposition of the correlation matrix. Computer code implementing the proposed algorithm supplements this article. A simulation study comparing MCS, LHS, maximinLHS and LHSMDU demonstrates that increased multidimensional uniformity can significantly improve realization efficiency and that LHSMDU is effective for large multivariate problems.  相似文献   
470.
Previous investigations of testosterone and externalizing behavior have provided mixed findings. We tested the hypothesis that self‐regulatory personality moderates the testosterone–externalizing behavior association in adolescence. Parents reported on their 13‐ to 18‐year‐old (= 106, Mage = 16.01, SD = 1.29) children's personalities and psychopathology. Testosterone was measured via drool samples. As hypothesized, personality moderated the testosterone–externalizing behavior association. High testosterone predicted higher levels of externalizing behaviors, but only for adolescents low in Agreeableness and Conscientiousness. Also, personality acted as a resiliency factor: high levels of Conscientiousness, in the presence of high testosterone, predicted lower levels of rule breaking. Results highlight how endogenous factors, such as personality, may interact with testosterone, and emphasize the relevance of including personality moderators in future research.  相似文献   
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