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991.
992.
Higher-order latent trait models for cognitive diagnosis   总被引:9,自引:0,他引:9  
Higher-order latent traits are proposed for specifying the joint distribution of binary attributes in models for cognitive diagnosis. This approach results in a parsimonious model for the joint distribution of a high-dimensional attribute vector that is natural in many situations when specific cognitive information is sought but a less informative item response model would be a reasonable alternative. This approach stems from viewing the attributes as the specific knowledge required for examination performance, and modeling these attributes as arising from a broadly-defined latent trait resembling theϑ of item response models. In this way a relatively simple model for the joint distribution of the attributes results, which is based on a plausible model for the relationship between general aptitude and specific knowledge. Markov chain Monte Carlo algorithms for parameter estimation are given for selected response distributions, and simulation results are presented to examine the performance of the algorithm as well as the sensitivity of classification to model misspecification. An analysis of fraction subtraction data is provided as an example. This research was funded by National Institute of Health grant R01 CA81068. We would like to thank William Stout and Sarah Hartz for many useful discussions, three anonymous reviewers for helpful comments and suggestions, and Kikumi Tatsuoka and Curtis Tatsuoka for generously sharing data.  相似文献   
993.
A consistent finding in coalition research is that the payoff of coalition members is related to (a) the resources they contribute to the coalition, and to (b) the number of alternative coalitions they can form. These two factors are, however, often intertwined. A greater number of resources tends to go hand in hand with a greater number of alternatives, leaving unanswered how both factors affect coalition behaviour. This paper attempts to clarify the interplay of resources and alternatives by disentangling the two in a newly developed coalition paradigm. Results indicated that participants base their payoff allocation on both resources and alternatives, but suggest that self‐serving behaviour is more related to alternatives. Furthermore, resources and alternatives had a distinct effect on the bargaining process. It was shown that differences in alternatives led to longer bargaining. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
994.
This article concerns the question how innovation is achieved in open source communities. Open source communities are collections of geographically distributed individuals, who volunteer or are paid to participate in the development of highly innovative software programs. These communities are argued to be self-organizing systems in which high levels of variation are achieved. Next, this article focuses on selection as part of innovation. It is shown that selection is achieved through a rather simple principle of copying and following tags. Four tags are identified and discussed and it is demonstrated how they lead to the selection of software among the great level of variety. Ruben van Wendel de Joode is a Ph.D. student. He is part of Betade, which is one of the Delft interfaculty research centers; and the Dutch Institute of Government (NIG), the research school for public administration and political science. His Ph.D. research, scheduled to be finished mid 2004, focuses on open source. He has published numerous articles on OSS.  相似文献   
995.
The term “evolution” is often used in the administrative sciences to designate dynamic processes of change in general. In biology, evolution has a very specific meaning, namely the application of a generative variation-selective retention scheme to change. Applying this to the administrative sciences is more exacting: describing what the variation consists of, how replication of the generated variation occurs and delineating the population from which the selection is made are far from easy. While it is the intention of this special issue as a whole to provide some empirical examples of evolutionary change in the public and private sectors, this introduction will lay out the main lines of thought in what is often referred to as universal Darwinism and what this means in the administrative sciences. Key concepts here are generative variation, selective retention, and selective institutional environment. According to the authors, the Darwinian scheme of evolutionary theory focuses on how new ideas or concepts arise, how they propagate and influence wider actor thinking and on how the institutional environment in which they operate affects their differential survival. This evolutionary process is an interplay between actors and replicators (sounds, images, and in this context mostly words) in which it cannot be said in advance which one is fooling the other. Martin De Jong is associate professor of public management. Haiko Van der Voort is a research associate who lectures and publishes on a wide range of issues including process management and system innovations.  相似文献   
996.
Process arrangements for variety,retention, and selection   总被引:1,自引:0,他引:1  
This article argues that process management aimed at introducing variety, retention, and selection into complex decision-making processes can make a substantial contribution to improving them. It also describes process arrangements for variety, retention, and selection. He received his Ph. D. in public administration at Erasmus University, Rotterdam. He is also program director at the Netherlands School of Public Administration and director of the TUD research program on multi actor systems. His research concerns networks and network-organizations, with a strong focus on governance and management issues in networks. He is the author on a number of internationally recognized books on these issues. His conceptual approach of these issues has been applied in research on the open source movement, frequency allocation, the design of policy instruments and mediation (e.g. interconnection disputes). He is program leader of the Bsik research program Next Generation Infrastructures. He holds the post of chair research within the faculty.  相似文献   
997.
In a sample of 129 Dutch 15‐month‐old infants, attachment security was assessed both with the Attachment Q‐Set (AQS; Waters, 1995) and with a short version of Ainsworth, Blehar, Waters, and Wall's (1978) Strange Situation (SSS). Infants classified as secure using the SSS had significantly higher AQS scores than insecure and disorganized infants in particular. At the AQS item level, disorganized infants were described as significantly more noncompliant, fussy, and angry relative to secure infants. When security as assessed using the SSS was controlled, the observed quality of parental interactive behavior, parental ego‐resilience, high levels of infant task orientation and pleasure, and low levels of infant anger proneness were found to explain significant and unique portions of the variance in the AQS security scores. The apparently unfavorable set of characteristics associated with low AQS security scores suggests such scores to predict later developmental problems. ©2004 Michigan Association for Infant Mental Health.  相似文献   
998.
Les prédicteurs et les composantes des attitudes envers le multiculturalisme ont étéétudies chez 341 Néerlandais tout‐venant. Les attitudes relèvent d’une structure unidimensionnelle, mais le niveau d’adhésion au multiculturalisme varie significativement selon les domaines. Le niveau culturel et le fait de vivre en ville avec peu d’immigrés étaient les seules variables positivement corrélées avec l’adhésion au multiculturalisme. Un modèle en pistes causales s’est révélé pertinent, les attitudes et les comportements dépendant des variables psychologiques suivantes; connaissances, satisfaction générale, perspectives d’avenir, désirabilité sociale et perception des normes sociales favorables au multiculturalisme ou en faisant au contraire une menace. Globalement, l’exclusion était désapprouvée par la majorité des Néerlandais, mais le pluralisme culturel nétait pas ressenti comme étant un atout précieux pour leur société, et ils nétaient pas disposés à faire beaucoup d’efforts pour faciliter l’intégration des minorités. Predictors and components of attitudes toward multiculturalism were studied in 341 native Dutch people. Attitudes were found to have a unidimensional structure, but the level of support for multiculturalism was found to vary significantly over societal domains. Level of education and living in city districts with few non‐natives were the only background variables that were (positively) related to support for multiculturalism. A path model, with psychological background variables (knowledge, life satisfaction, life opportunities, perceived social norms about multiculturalism as a threat and support for multiculturalism, and social desirability) predicting attitudes and behavior, showed a good fit. Generally, exclusionist positions were not endorsed by majority Dutch, but cultural pluralism was not seen as a valuable asset of their society, and they are not inclined to put much effort into minority integration.  相似文献   
999.
There are sufficient reasons to conclude that virtual education is not just hype. There are, among others, economic motivations such as bringing one learning module to a larger audience of learners, and pragmatic reasons such as achieving flexibility in time and space for learning, which is especially important for adult learners. However, from a pedagogic point of view there are some doubts. Current technologies meant for learning and working in teams are often designed for functional collaboration (e.g., sharing documents, communicating), but fail to support learning, understanding and team forming (e.g., carrying out pedagogically adequate tasks, understanding each other's work and group dynamic processes) in virtual teams. In order to understand virtual teams, we need to know how we can study learning and understanding in virtual teams. Interesting research questions are: Which concepts are important in understanding virtual teams? How can we measure those concepts, and in what type of setting (e.g., experimental study, case study)? The aim of this special issue is to provide and discuss concepts and pragmatic insights in research on learning and understanding in virtual teams. The aim of this article is to set the stage for those articles.  相似文献   
1000.
Contextualist moral philosophers criticise hands-off liberal theories of justice for abstracting from the cultural context in which people make choices. Will Kymlicka and Joseph Carens, for example, demonstrate that these theories are disadvantageous to cultural minorities who want to pursue their own way of life. I argue that Pierre Bourdieu's critique of moral reason radicalises contextualist moral philosophy by giving it a sociological turn. In Bourdieu's view it is not enough to provide marginalised groups or subgroups with equal access to public institutions and specific cultural rights—in some cases this may in fact be detrimental. He contends that scientists, politicians and other intellectuals have a duty to take seriously the social presuppositions of free deliberate choice and public opinion and to support cultural minorities with instruments to liberate themselves from their often precarious situation.  相似文献   
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