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991.
The main goal of this study was to examine the direct and moderating effects of trustworthiness and modeling on adolescent siblings' adjustment. Data were collected from 438 families including a mother, a younger sibling in fifth, sixth, or seventh grade (M = 11.6 years), and an older sibling (M = 14.3 years). Respondents completed Web‐based surveys describing sibling conflict and warmth. Siblings reported on trustworthiness and modeling, and mothers described adjustment. Sibling conflict was directly associated with internalizing and externalizing behaviors for both siblings. The older siblings' reports of trustworthiness were directly associated with the outcome measures. The younger siblings' reports of trustworthiness were less directly associated, but a possible salutary effect was most evident under the highest levels of sibling conflict or warmth. Higher sibling modeling was a risk factor for adjustment problems in relations characterized by high conflict. Results support exploring trustworthiness as a key dimension of sibling relations. 相似文献
992.
Cary J. Roseth Anthony D. Pellegrini Danielle N. Dupuis Catherine M. Bohn Meghan C. Hickey Caroline L. Hilk Annie Peshkam 《Social Development》2011,20(1):185-211
Bistrategic resource control entails using both coercive and prosocial strategies in competition for resources. The present study sought to clarify whether bistrategic involves more than simply using both strategies some of the time. Examining 88 preschoolers' coercion and prosociality over an entire school year, results showed that coercive resource control was used most frequently at the start of the school year, presumably to access resources and establish social dominance. Rates of prosocial resource control increased over the school year, and socially dominant preschoolers showed higher rates compared with peers, presumably to maintain resource control while keeping peers as allies. Socially dominant preschoolers also used reconciliation more often than peers, resulting in higher rates of affiliation between former competitors and more positive peer regard from fall to spring. Findings are discussed in terms of resource control theory and the importance of situating social behaviors within the behavioral and relationship context in which they are embedded. 相似文献
993.
High species diversity is argued to be the most important requisite for a resilient urban forest. In spite of this, there are many cities in the northern hemisphere that have very limited species diversity within their tree population. Consequently, there is an immense risk to urban canopy cover, if these over-used species succumb to serious pests or pathogens. Recognition of this should motivate the use of less commonly used species. Analysis of plant traits, such as the leaf water potential at turgor loss (ΨP0), can provide useful insights into a species’ capacity to grow in warm and dry urban environments. Therefore, the aim of this study was to evaluate ΨP0 of 45 tree species, the majority of which are rare in urban environments. To help evaluate the potential for using ΨP0 data to support future decision-making, a survey of professionals engaged with establishing trees in urban environments was also used to assess the relationship between the measured ΨP0 and the perceived drought tolerance of selected species. This study demonstrates that ΨP0 gives strong evidence for a species’ capacity to tolerate dry growing conditions and is a trait that varies substantially across species. Furthermore, ΨP0 was shown to closely relate to the experience of professionals involved in establishing trees in urban environments, thus providing evidence of its practical significance. Use of plant traits, such as ΨP0, should, therefore, give those specifying trees confidence to recommend non-traditional species for challenging urban environments. 相似文献
994.
Alice B. M. Vadrot Aleksandar Rankovic Renaud Lapeyre Pierre-Marie Aubert Yann Laurans 《Innovation: The European Journal of Social Science Research》2018,31(1):S78-S100
Despite the increased attention, which has been given to the issue of involving knowledge and experts from the social sciences and humanities (SSH) into the products and works of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), little is known on what the expectations towards the involvement of SSH in IPBES actually are. The aim of this paper is to close this gap by identifying the range of possible SSH contributions to IPBES that are expected in the literature, and discuss the inherent challenges of and concrete ways to realize these contributions in the particular institutional setting of IPBES. We address these two points by: firstly, assessing the literature dealing with IPBES and building a typology describing the main ways in which contributions from SSH to IPBES have been conceived between 2006 and 2017. We discuss these expected contributions in light of broader debates on the role of SSH in nature conservation and analyse some of the blind spots and selectivities in the perception of how SSH could substantially contribute to the works of IPBES. Then, secondly, by looking at one particular example, economics and its use in the first thematic assessment on pollinators, pollination and food production, we will concretely illustrate how works in a given discipline could contribute in many different and unprecedented ways to the works of IPBES and help identify paths for enhancing the conservation of biodiversity. Finally, we propose a range of practical recommendations as to how to increase the contribution of SSH in the works of IPBES. 相似文献
995.
Jeffrey L. Andrews Paul D. McNicholas 《Journal of statistical planning and inference》2011,141(4):1479-1486
A novel family of mixture models is introduced based on modified t-factor analyzers. Modified factor analyzers were recently introduced within the Gaussian context and our work presents a more flexible and robust alternative. We introduce a family of mixtures of modified t-factor analyzers that uses this generalized version of the factor analysis covariance structure. We apply this family within three paradigms: model-based clustering; model-based classification; and model-based discriminant analysis. In addition, we apply the recently published Gaussian analogue to this family under the model-based classification and discriminant analysis paradigms for the first time. Parameter estimation is carried out within the alternating expectation-conditional maximization framework and the Bayesian information criterion is used for model selection. Two real data sets are used to compare our approach to other popular model-based approaches; in these comparisons, the chosen mixtures of modified t-factor analyzers model performs favourably. We conclude with a summary and suggestions for future work. 相似文献
996.
We introduce a general Monte Carlo method based on Nested Sampling (NS), for sampling complex probability distributions and
estimating the normalising constant. The method uses one or more particles, which explore a mixture of nested probability
distributions, each successive distribution occupying ∼e
−1 times the enclosed prior mass of the previous distribution. While NS technically requires independent generation of particles,
Markov Chain Monte Carlo (MCMC) exploration fits naturally into this technique. We illustrate the new method on a test problem
and find that it can achieve four times the accuracy of classic MCMC-based Nested Sampling, for the same computational effort;
equivalent to a factor of 16 speedup. An additional benefit is that more samples and a more accurate evidence value can be
obtained simply by continuing the run for longer, as in standard MCMC. 相似文献
997.
Objective. Research on widespread loan failures suggests that many of the mortgage loans that were made since 2000 were of a deceptive or predatory nature. This study explores the experiences and sentiments of those who are at risk of foreclosure within a broader framework of trust, individualization, and ontological security. Methods. Interviews examine families' lending experience and how they have coped with their personal troubles that resulted from their housing crisis. Results. As many of these loans were of a deceptive or predatory nature, individuals are likely to reflect on the psychological consequences of their predicament. Although these findings suggest that these individuals have lost trust in the housing market, many have internalized their situation as a personal failure. In addition, feelings of anxiety, stress, insecurity, and uncertainty have come to characterize their experiences. Conclusions. This research calls for policy recommendations that seek to restore confidence and to ensure greater consumer protection in financial markets. 相似文献
998.
We propose that Bayesian variable selection for linear parametrizations with Gaussian iid likelihoods should be based on the spherical symmetry of the diagonalized parameter space. Our r-prior results in closed forms for the evidence for four examples, including the hyper-g prior and the Zellner–Siow prior, which are shown to be special cases. Scenarios of a single-variable dispersion parameter and of fixed dispersion are studied, and asymptotic forms comparable to the traditional information criteria are derived. A simulation exercise shows that model comparison based on our r-prior gives good results comparable to or better than current model comparison schemes. 相似文献
999.
1000.