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101.
Four pigeons responded on a two-component multiple token-reinforcement schedule, in which tokens were produced according to a random-interval 30-sec schedule and exchanged according to a variable-ratio 4 schedule in both components. To assess the effects of contingent token loss, tokens were removed after every second response (i.e., fixed-ratio 2 loss) in one of the components. Response rates were selectively lower in the loss components relative to baseline (no-loss) conditions, as well as to the within-condition no-loss components. Response rates were decreased to a greater degree in the presence of tokens than in their absence. To control for the effects of changes in the density of token and food reinforcement, two parts consisted of additional conditions where food density and token loss were yoked to those in a previous loss condition. In the yoked-food condition, tokens were produced as usual in both components, but the overall density of food reinforcement in one of the components was yoked to that obtained during a previous token-loss condition. In the yoked token-loss condition, tokens were removed during one component of the multiple schedule at a rate that approximately matched the obtained rate of loss from a previous token-loss condition. Response rates in these yoked components were less affected than those in comparable loss components, despite similar densities of token, exchange, and food reinforcement. On the whole, the results support the conclusion that contingent token loss serves as an effective punisher with pigeons.  相似文献   
102.
Based on the complex dispersion relation for the two-dimensional free-surface waves generated by a moving body in the steady Oseen flows, the effect of viscosity on wavelength and wave amplitude was investigated by means of an asymptotic method and a numerical analysis. A comparison between the asymptotic and numerical analysis for the viscous decay factor demonstrates the validity of the perturbation expansions for the wave profile. The numerical result shows that the wavelength of viscous wave is slightly elongated in comparison with that of inviscid wave.  相似文献   
103.
104.
This study explores the reflective processes by which a grade 5 science community co-constructed shared inquiry structures to focus and guide its inquiry about human body systems over a school year supported by a collaborative online environment. The co-constructed structures included a list of collective wondering areas as the shared focus of inquiry and models of the inquiry process in the form of “research cycle.” Qualitative analyses of field notes, classroom videos, student notebooks and interviews elaborate the evolution of the inquiry areas and the “research cycle” model as well as students’ adaptive use of the structures to guide deeper inquiry. Content analyses of students’ individual research questions and collaborative online discourse indicate that students used the structures to develop more advanced inquiry and make productive contributions. The results contribute to elaborating a reflective structuration approach to co-organizing and sustaining long-term, open-ended inquiry in knowledge building communities.  相似文献   
105.
The Occupational Information Network (O*NET) is the primary source of occupational information in the United States (US). In this study, I review O*NET’s usage for career guidance in India and conceive a career intervention based on it. In an empirical evaluation adopting a posttest-only experimental design with post-graduate management students (N = 220), effectiveness of the career intervention in reducing career decision-making difficulties is presented. An important cultural insight the study offers regarding occurrence of career decision-making difficulties, are the differences due to vertical–horizontal characteristics, apart from the more researched individualism–collectivism characteristics.  相似文献   
106.
There has been increasing recognition for the need to reform doctoral training practices to foster students’ personal epistemology. This study describes the design and evaluation of a learning experience designed to help students understand the scholarly publication process. Firstly, this study discusses the design of the learning experience, describing the collaborative process of writing an interdisciplinary publication using both online and face-to-face learning. Secondly, this study evaluates the effectiveness of the learning experience by examining students’ reflections. We show that participation in the learning experience helped students to develop their academic writing proficiency, collaboration and teamwork, intercultural competence, and ability to engage in reflective practice. Importantly, we show that each student also created more individualised knowledge, gaining insight into how they and others think. This study, therefore, demonstrates that personal epistemology can be fostered through collaboration in a doctoral writing group context.  相似文献   
107.
In der Entscheidung Morgan und Bucher hat der Europäische Gerichtshof zwei Regelungen des deutschen Bundesausbildungsförderungsgesetzes zur Ausbildungsförderung für Auslandsstudien als gegen die Freizügigkeit der Unionsbürger nach Art 18 EGV verstoßend und somit gemeinschaftsrechtswidrig angesehen. Das Urteil unterstreicht die Bedeutung, die der Gerichtshof der Freizügigkeit und der Gleichbehandlung von Unionsbürgern im Bildungsbereich zuerkennt. Dies wird von Österreich auch bei Klärung der Hochschulzugangsproblematik zu berücksichtigen sein. Das durch eine Novelle zum österreichischen Studienförderungsgesetz eingeführte Mobilitätsstipendium ist entsprechend den vom Europäischen Gerichtshof in Morgan und Bucher entwickelten Grundsätzen am Gemeinschaftsrecht zu messen.  相似文献   
108.
Using national survey data and discrete-time logit modeling, this research seeks to understand whether student aid mediates the relationship between parental income and student dropout behavior. Our analysis confirms that there is a gap in dropout rates for low-income students compared with their upper income peers, and suggests that some types of aid are associated with lower risks of dropout. Thus, we examine the interaction between financial aid type and parental income to explore whether, and if so how, different types of aid may reduce the dropout gap by income level group. We find that the receipt of a Pell grant is related to narrowing the dropout gap between students from low- and middle-income groups, although overall the interaction between Pell grant and income is not significant. Loans and work-study aid both have similar effects on student dropout across all income groups. Methodologically, our results demonstrate the need to model dropout behavior temporally and to avoid main-effect bias by incorporating interaction effects.
Stephen L. DesJardinsEmail:
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109.
New Caledonian crows make and use tools, and tool types vary over geographic landscapes. Social learning may explain the variation in tool design, but it is unknown to what degree social learning accounts for the maintenance of these designs. Indeed, little is known about the mechanisms these crows use to obtain information from others, despite the question’s importance in understanding whether tool behavior is transmitted via social, genetic, or environmental means. For social transmission to account for tool-type variation, copying must utilize a mechanism that is action specific (e.g., pushing left vs. right) as well as context specific (e.g., pushing a particular object vs. any object). To determine whether crows can copy a demonstrator’s actions as well as the contexts in which they occur, we conducted a diffusion experiment using a novel foraging task. We used a nontool task to eliminate any confounds introduced by individual differences in their prior tool experience. Two groups had demonstrators (trained in isolation on different options of a four-option task, including a two-action option) and one group did not. We found that crows socially learn about context: After observers see a demonstrator interact with the task, they are more likely to interact with the same parts of the task. In contrast, observers did not copy the demonstrator’s specific actions. Our results suggest it is unlikely that observing tool-making behavior transmits tool types. We suggest it is possible that tool types are transmitted when crows copy the physical form of the tools they encounter.  相似文献   
110.
There is, broadly speaking, an agreement within the international science education community that comprehension of the nature of science (NOS) should be a key element in the scientific literacy of citizens. During the last few decades, several didactic approaches have emerged concerning what and how to teach NOS. Also, one of the basic objectives of science education is for students to become familiar with the skills typical of scientific practice; however, there is little reference to their need to also acquire meta-knowledge about scientific practice (i.e., an understanding of the nature of scientific practice). Among other reasons, this may be due to NOS being essentially identified in most of the predominant proposals with the nature of scientific knowledge. But why not plan the teaching of science to be in tune with real scientific practice for students to learn about the nature of scientific practice at the same time as they are learning science? The answer to this question has given rise to a proposal grounded in ten essential pedagogical principles for the teaching and learning of science in secondary school. These are the principle of formulating questions, the principle of creativity and imagination, the principle of experimentation, the principle of procedural diversity, the principle of errors as opportunity, the principle of modeling, the principle of cooperation and teamwork, the principle of argumentation and discussion, the principle of communication, and the principle of evaluation. The purpose of this article is to present the justification and fundaments of these principles.  相似文献   
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