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31.
Peer nominations, a central method for measuring peer relationships in developmental research, typically involve asking children or adolescents to choose peers who fit various criteria from an alphabetized roster of classmates or grade‐mates. Although such measures have been used for decades, very little research has investigated the effects of alphabetical name order on the number of nominations received by peers. This study collected peer nominations for 20 items among 607 eighth grade participants in two schools. Regression analyses showed that earlier name order significantly predicted higher nomination counts for eight of the items, and explained over 5 percent of the variance in four affective variables (friendship, acceptance, acquaintanceship, and received liking). Across variables, name order effects were negatively correlated with internal reliability of nominations, implying that order effects may be related to the consensus of the peer group. Name order also had a minimal effect on inter‐correlations among a subset of variables. Implications and concrete recommendations for controlling and reducing name order effects in future research are discussed. 相似文献
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Simon-Rusinowitz L Marks LN Loughlin DM Desmond SM Mahoney KJ Zacharias BL Squillace MR Allison AM 《Journal of aging & social policy》2002,14(3-4):95-118
An increasing number of aging community providers and consumers support consumer-direction (CD) in long-term care services. In regard to devolution, consumer-direction goes beyond the usual approach of shifting responsibilities from the federal government to state governments to bring programs "closer to the people." Consumer-direction goes even further by placing resources directly in the hands of consumers. Yet, many questions remain unanswered regarding how to implement CD personal assistance services in general, and especially for older persons. This article describes the importance of examining views from multiple key stakeholders involved in implementing CD programs. We report on three background studies that have informed the Cash and Counseling Demonstration and Evaluation (CCDE) design and implementation-policy expert interviews as well as surveys and focus groups with consumers and representatives. As a fourth data source, we drew upon experiences in designing the CCDE and initial results from the first year of implementation. Each of the three studies on its own provided essential information for planning the CCDE. However, when we examined the studies together, and added CCDE design and implementation experiences, views expressed by the different stakeholders formed a type of multi-perspective "dialogue" that expanded our knowledge about implementing CD services. We hope this increased knowledge will help expand the availability of such services for consumers of any age who want to direct their own care. 相似文献
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Business success in the 21st century will be based on the widespread mastery of leadership roles, rather than on the directives of a professional or leadership elite. The first step for systematically enacting a leadership development agenda for our nation is to identify the factors, values or qualities most important to leadership effectiveness. Next, we must improve our understanding of how these guiding ideas and insights translate into what successful leaders do. As we perfect this understanding, we will need to operationally define the best practices of successful leaders. These best practices must then become benchmarks for intensive leadership development efforts.This article considers nine methodological challenges of the first agenda item-identification of the factors, values or qualities most important to leadership effectiveness. To illustrate these challenges, the authors use their own business leadership research as a case study. This research surveys 127 chairmen, chief executive officers, and presidents-a cross section of successful U.S.A. business leaders, including men and women from all parts of the nation who have diverse industry, racial, ethnic and religious backgrounds. The authors identify where methodological improvements are needed to cope with the challenges of leadership research. They suggest important directions for methodological development and propose three minimum standards for future leadership research. 相似文献
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N. Bourgeois A. Giannakos G. Lucarelli I. Milis V. T. Paschos O. Pottié 《Journal of Combinatorial Optimization》2012,23(1):94-117
In this paper, we deal with the problem of finding quasi-independent sets in graphs. This problem is formally defined in three
versions, which are shown to be polynomially equivalent. The one that looks most general, namely, f-max quasi-independent set, consists of, given a graph and a non-decreasing function f, finding a maximum size subset Q of the vertices of the graph, such that the number of edges in the induced subgraph is less than or equal to f(|Q|). For this problem, we show an exact solution method that runs within time
O*(2\fracd-27/23d+1n)O^{*}(2^{\frac{d-27/23}{d+1}n}) on graphs of average degree bounded by d. For the most specifically defined γ-max quasi-independent set and k-max quasi-independent set problems, several results on complexity and approximation are shown, and greedy algorithms are proposed, analyzed and tested. 相似文献
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以TEECE创建的技术创新资源获取机制理论框架为研究起点,进行了开放式创新背景下的拓展。根据其对技术资源与商业化资源的划分,运用"占有机制"与"合约交易"2个关键变量,分别揭示在封闭式创新模式向开放式创新模式转变过程中,创新资源获取机制本质由创新资源控制权拓展为创新资源联合共享,具体表现为2个方面:一是技术资源占有机制由正式制度拓展为正式制度与非正式制度的集合,从而其作用机理从环境决定的外生变量,拓展为企业内生性的战略选择;二是商业化资源交易契约从合约交易拓展为合约交易与嵌入式交易。 相似文献
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长三角地区节能减排演化情景分析及预测 总被引:2,自引:0,他引:2
以长三角地区经济发展为基础,综合考虑该地区能源环境现状。基于节能减排动态演化模型,结合情景分析法对长三角地区2015年经济产值、能源消耗及污染排放进行预测,并分析2009~2015年经济产值、能源消耗及污染排放演化情况。旨在为未来长三角地区实施节能减排策略,实现可持续发展提供理论依据。 相似文献
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This paper analyses how network embeddedness affects the exploration and exploitation of R&D project performance. By developing joint projects, partners and projects are linked to one another and form a network that generates social capital. We examine how the location, which determines the access to information and knowledge within a network of relationships, affects the performance of projects. We consider this question in the setup of exploration and exploitation projects, using a database built from an EU framework. We find that each of the structural embeddedness dimensions (degree, betweenness and eigenvector centrality) have a different impact on the exploration and exploitation project performance. Our empirical analysis extends to project management literature and social capital theory, by including the effect that the acquisition of external knowledge has on the performance of the project. 相似文献