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This article explores the relationship between parental psychological control and parental autonomy granting, and the relations between these constructs and indicators of adolescent psychosocial functioning, in a sample of 9,564 adolescents from grades 9 to 12. Participants completed a comprehensive parenting questionnaire as well as several measures of psychosocial adjustment. Confirmatory factor analyses of the parenting items revealed discrete factors for psychological control and autonomy granting, suggesting that these are distinct parenting constructs rather than opposite ends of a parental control continuum. Moreover, structural equation modeling showed that these factors were weakly correlated and differentially related to adolescent internalizing symptoms. Findings have implications for future conceptualization and measurement of psychological control and autonomy granting, and for research examining their effects on adolescent development.  相似文献   
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How do firm-specific, demand-related factors influence the relationship between intra-industry diversification (IID) and performance? Recent findings regarding the performance effects of IID depict a complex picture with curvilinear relationships and several contingencies. However, firm-specific contingencies on the demand side have remained unexplored. We analyze how IID relates to firm performance (market share) in the German automotive industry using panel data between 1999 and 2008. We specifically focus on a firm's high-quality brand image as a demand-side contingency. We find support for our hypotheses of complex curvilinear relationships as well as for moderating effects of brand quality. Our results have significant theoretical implications for the IID literature.  相似文献   
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We present tight upper and lower bounds for the traveling salesman path through the points of two-dimensional modular lattices. We use these results to bound the traveling salesman path of two-dimensional Kronecker point sets. Our results rely on earlier work on shortest vectors in lattices as well as on the strong convergence of Jacobi–Perron type algorithms.  相似文献   
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Two fundamental axioms in social choice theory are consistency with respect to a variable electorate and consistency with respect to components of similar alternatives. In the context of traditional non‐probabilistic social choice, these axioms are incompatible with each other. We show that in the context of probabilistic social choice, these axioms uniquely characterize a function proposed by Fishburn (1984). Fishburn's function returns so‐called maximal lotteries, that is, lotteries that correspond to optimal mixed strategies in the symmetric zero‐sum game induced by the pairwise majority margins. Maximal lotteries are guaranteed to exist due to von Neumann's Minimax Theorem, are almost always unique, and can be efficiently computed using linear programming.  相似文献   
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Provisions of the Adoption and Safe Families Act of 1997 mandated shorter time frames for making permanency decisions and facilitating adoption. Yet for many children, foster care continued to be a significant portion of their life experiences. This project explored the potential permanency option of birthfamilies and extended kin for children who languished in foster care while being free for adoption. Eighteen children achieved permanent placement with their birthfamilies. In addition, staff found that although many families could not provide permanent placements, they could offer appropriate relationships with the children. This project team recommends viewing family relationships as an integral component where placement is one option on a continuum that includes letters, phone calls, and visits.  相似文献   
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The relative influence of perceived familial addictive behaviors and personal gambling behaviors on adolescents' self-perceptions of gambling problems was examined. Students from five high schools in Connecticut (N = 3,886) were surveyed. Of those between the ages of 14 and 17 who scored two or more on the South Oaks Gambling Screen--Revised for Adolescents (n = 532; 72% male; 43% Caucasian), 14.3% reported having a current or past problem with gambling. Wagering larger amounts in a single day, gambling on a daily basis, and perceived presence of a family member with a gambling problem were associated with increased odds of self-perception of a gambling problem. Thus, adolescents who may be less likely to be identified for prevention efforts (due to lack of engagement in high stakes gambling or the real/perceived absence of a problematic gambler in the home) appear less likely to perceive a gambling problem. To advance prevention and treatment strategies, the apparent discrepancy between adolescents' self-perceptions and objective reports of problem gambling behaviors warrants further investigation.  相似文献   
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In confirmatory clinical trials, the prespecification of the primary analysis model is a universally accepted scientific principle to allow strict control of the type I error. Consequently, both the ICH E9 guideline and the European Medicines Agency (EMA) guideline on missing data in confirmatory clinical trials require that the primary analysis model is defined unambiguously. This requirement applies to mixed models for longitudinal data handling missing data implicitly. To evaluate the compliance with the EMA guideline, we evaluated the model specifications in those clinical study protocols from development phases II and III submitted between 2015 and 2018 to the Ethics Committee at Hannover Medical School under the German Medicinal Products Act, which planned to use a mixed model for longitudinal data in the confirmatory testing strategy. Overall, 39 trials from different types of sponsors and a wide range of therapeutic areas were evaluated. While nearly all protocols specify the fixed and random effects of the analysis model (95%), only 77% give the structure of the covariance matrix used for modeling the repeated measurements. Moreover, the testing method (36%), the estimation method (28%), the computation method (3%), and the fallback strategy (18%) are given by less than half the study protocols. Subgroup analyses indicate that these findings are universal and not specific to clinical trial phases or size of company. Altogether, our results show that guideline compliance is to various degrees poor and consequently, strict type I error rate control at the intended level is not guaranteed.  相似文献   
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