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941.
Mary Lynne Courtney Robert Cohen Daneen P. Deptula Katherine M. Kitzmann 《Social Development》2003,12(1):46-66
We experimentally examined social contextual factors that might moderate children's dislike for aggressors and for victims of aggression, by varying both the aggressor's behavior (aggressive toward multiple children versus aggressive only toward one child) and the victim's behavior (passive versus assertive). Children (117 male and female fourth to sixth graders) listened to one of four scenarios describing the experiences of boys at a summer camp and rated how much they liked the aggressor, the victim, and the other children in the scenario; children also reported how much they thought the aggressor, victim, and others liked each other. Overall, and consistent with previous research, children disliked aggressors the most, followed by victims and then by the other children in the scenarios. Importantly, children's liking was influenced by the social context in which the aggression occurred, particularly in regards to how the victim responded. Aggressors (general or focused) were liked more if their victim was assertive rather than nonassertive. Furthermore, children liked nonassertive victims less than assertive victims, particularly a nonassertive victim in response to a general aggressor. Inferred liking among the group members also was dependent on the social context of the provocation. This research highlights the need to consider aggression as more than a set of behaviors. Aggression is a social event embedded within a social context and interpersonal relationships must be considered. 相似文献
942.
Alan B. Franklin David R. Anderson Kenneth P. Burnham 《Journal of applied statistics》2002,29(1-4):267-287
We obtained banding and recovery data from the Bird Banding Laboratory (operated by the Biological Resources Division of the US Geological Survey) for adults from 129 avian species that had been continuously banded for > 24 years. Data were partitioned by gender, banding period (winter versus summer), and by states/provinces. Data sets were initially screened for adequacy based on specific criteria (e.g. minimum sample sizes). Fifty-nine data sets (11 waterfowl species, the Mourning Dove and Common Grackle) met our criteria of adequacy for further analysis. We estimated annual survival probabilities using the Brownie et al. recovery model {St, ft} in program MARK. Trends in annual survival and temporal process variation were estimated using random effects models based on shrinkage estimators. Waterfowl species had relatively little variation in annual survival probabilities (mean CV = 8.7% and 10% for males and females, respectively). The limited data for other species suggested similar low temporal variation for males, but higher temporal variation for females (CV = 40%). Evidence for long-term trends varied by species, banding period and sex, with no obvious spatial patterns for either positive or negative trends in survival probabilities. An exception was Mourning Doves banded in Illinois/Missouri and Arizona/New Mexico where both males (slope = -0.0122, se = 0.0019 and females (slope = -0.0109 to -0.0128, se = 0.0018 -0.0032) exhibited declining trends in survival probabilities. We believe our approach has application for large-scale monitoring. However, meaningful banding and recovery data for species other than waterfowl is very limited in North America. 相似文献
943.
P. J. Brown M. Vannucci T. Fearn 《Journal of the Royal Statistical Society. Series B, Statistical methodology》2002,64(3):519-536
Summary. When a number of distinct models contend for use in prediction, the choice of a single model can offer rather unstable predictions. In regression, stochastic search variable selection with Bayesian model averaging offers a cure for this robustness issue but at the expense of requiring very many predictors. Here we look at Bayes model averaging incorporating variable selection for prediction. This offers similar mean-square errors of prediction but with a vastly reduced predictor space. This can greatly aid the interpretation of the model. It also reduces the cost if measured variables have costs. The development here uses decision theory in the context of the multivariate general linear model. In passing, this reduced predictor space Bayes model averaging is contrasted with single-model approximations. A fast algorithm for updating regressions in the Markov chain Monte Carlo searches for posterior inference is developed, allowing many more variables than observations to be contemplated. We discuss the merits of absolute rather than proportionate shrinkage in regression, especially when there are more variables than observations. The methodology is illustrated on a set of spectroscopic data used for measuring the amounts of different sugars in an aqueous solution. 相似文献
944.
21世纪是知识经济的时代。知识要素和人力资源 (即人才 )是知识经济的两个重要因素 ,知识的传播和人才的培养都离不开教育。该文以国家创新系统的人才层次结构为依据 ,提出林业创新系统的人才层次结构和林业创新人才的层次结构 ,并通过分析北京林业大学历年教师、学生的数据 ,得出在中国林业发展的三大阶段中林业创新人才培养的实际结构和未来结构 ,指出在知识创新的情况下 ,培养未来林业人才的趋势 相似文献
945.
Models of incomplete information have played a major role in the fields of political science and political economy. The models have almost exclusively been signaling models, and their substantive focus is frequently on situations in which the extensive form is not dictated by institutional requirements or procedures. We explore the relation between multiple-sender signaling games and the corresponding screening or mechanism design games without transfers and establish an equivalence result. If there is a fully-revealing equilibrium in the signaling game there is also a full-information optimal mechanism that yields the principal’s optimal policy in every state. The converse, that fully-revealing equilibria exist in the signaling game if a full-information optimal mechanism exists, is true if and only if the mechanism involves only the selection of policies that are optimal for some belief about the state. We also present two straightforward sufficient conditions for the existence of full-information optimal mechanisms. When either holds, fully-revealing equilibria in the signaling and screening games exist. The perceived advantage of the signaling over the screening approach – that no commitment by the principal is assumed – may be over-stated as flexibility in specifying off the path beliefs can mimic commitment. 相似文献
946.
袁明英 《北京林业大学学报(社会科学版)》2004,(Z1)
图书馆是高校的重要组成部分 ,其管理状况和作用的发挥关系到所在高校全局的发展。为了搞好图书馆建设 ,公共调查是一项经常性、基础性的工作。该文从高校图书馆公共调查的一般指标和方法的角度 ,结合高校图书馆的特点 ,提出了公共调查的一般思路、各业务板块的调查指标和方法设计及图书馆综合调查的要求和结构 相似文献
947.
It is argued that the abstract product attributes that consumers mention in a research setting should not be interpreted as combinations of the more concrete attributes consumers mention. Results from a laddering study show that a majority of elicited abstract product attributes are unrelated to concrete attributes. Furthermore, these unrelated abstract attributes are about different product aspects than the related abstract attributes. These findings are discussed in the light of the problem of ‘actionability', and of models for new product development. 相似文献
948.
Carla P. Davis 《The International migration review》2004,38(2):450-469
It is frequently noted that Cubans living in Miami are successful because they benefit from the formation of an enclave economy. Using the 1990 Census Public Use Microdata, this study broadens the examination beyond Miami to address the question of why Cubans living elsewhere have higher earnings than those in Miami. Specifically, I address the question of whether there is a relationship between Cuban ethnic enclave participation and Cuban income. Findings indicate that Cubans in Miami have the lowest personal income. Cubans living in areas with the lowest Cuban populations have the highest incomes. These findings are evidence against the enclave economy hypothesis. 相似文献
949.
王泽福 《北京林业大学学报(社会科学版)》2004,(Z1)
建设国际知名、国内高水平多科性研究型大学已成为北京林业大学的办学指导思想和奋斗目标 ,因此 ,图书馆面临着服务对象、服务内容、服务方式、服务针对性、服务层次等 5个方面的职能转换。针对形势变化和学校建设的需求 ,该文提出了图书馆在 4个方面的建设对策 :①建设研究型特色图书馆 ;②建设能提供深层次、全方位的文献信息导航服务的导航体系 ;③对文献信息资源进行重组和优化配置 ,建设特色馆藏 ;④启动支撑学科建设尤其是重点学科建设的“数字图书馆工程项目”。 相似文献
950.
孟莉 《北京林业大学学报(社会科学版)》2004,(Z1)
知识经济的核心是知识创新 ,而知识创新要求高等教育必须培养造就一批高素质的创新人才。数字化图书馆是高校图书馆发展的必然趋势。建设数字化图书馆对培养造就高素质的创新人才具有不可替代的重要作用。该文论述了数字化图书馆的概念、特征及其对培养高素质创新人才的重要作用 ,并提出了面向培养创新人才的数字化图书馆的建设方略 相似文献