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991.
This article attempts to characterize the general problem of selecting methods for decision-making. The traditional rational approach to choice is from economics, which offers expected-value maximization. The task environment of decision method selection, however, does not seem to provide the data necessary for carrying out the expected-value calculations. Our approach uses methods from the field of cognitive science. We develop the notion of domain size in fields such as chess, borrowing the concept of a chunk from human memory. We then develop a heuristic rule for choiceamongmethods. We propose this rule as one of many possible rules. 相似文献
992.
993.
Exploring the Effects of Financial Aid on the Gap in Student Dropout Risks by Income Level 总被引:1,自引:0,他引:1
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.
相似文献
Stephen L. DesJardinsEmail: |
994.
Corina J. Logan Alexis J. Breen Alex H. Taylor Russell D. Gray William J. E. Hoppitt 《Learning & behavior》2016,44(1):18-28
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
995.
996.
997.
Michael L. Lopez Louisa B. Tarullo Steven R. Forness Cheryl A. Boyce 《Early education and development》2000,11(3):265-282
Serving low-income children from birth to age five and their families, Head Start is a primary venue for identification and intervention in the area of child mental health. However, recent research has demonstrated that the knowledge base regarding prevalence, developmental course, and predictive power of child mental health problems is lacking for young children in general and low-income, diverse populations in particular. Head Start's agency-level data is often discrepant from both national estimates and small, intensive studies of similar populations, perhaps for reasons related to availability of community services and professional staff, as well as concerns about stigmatization. Following on recent expert recommendations, new collaborative Federal initiatives are underway to increase our understanding of the types, trajectories, and treatments of mental health problems affecting the vulnerable children served by Head Start. The paper concludes with a call to action for the field in the area of young children's mental health. 相似文献
998.
The purpose of this study is twofold: first, to examine to what extent the time students work on paid jobs is related to study‐time (class attendance and time devoted to self‐study) and second, to what extent the time students work on paid jobs is related to achievement. A number of 120 students from the problem‐based Faculty of Health Sciences in the Netherlands kept a time‐diary. Academic achievement was measured by using scores on the block‐test. The results showed that working about four to eight hours per week on paid jobs (as opposed to working less than four hours per week or to working intensively, more than 8 hours per week) actually is positively related to study‐time. Test‐scores are not significantly different among students who are not working on jobs, work some hours, or work a lot. 相似文献
999.
Leonard J. Waks 《Journal of Educational Change》2003,4(4):383-418
Globalization, unlike 20th century social and economic developments, will cause fundamental rather than merely incremental educational change. `Globalization' refers to a complex of technological and economic factorsincluding the global spread of communicationtechnology networks, and the global integration ofproduct and labor markets.I argue that (1) there is a powerful new alliance among elites and educational consumers for fundamental change; (2) globalization destabilizes the internal processes of school organizations that constrain fundamental change,motivating educators to innovate; (3) globalization erodes the institutional categories of public discourse that hold standard school practice in place, allowing a `shadow institution' of non-standard educational agencies to form; and (4) new synthetic visions of educational institutions in better accord with models of rational action in networked environments, are being formulated; and (5) these are now guiding a convergence of piecemeal innovations towards a fundamentally transformed institutional pattern. 相似文献
1000.
Children's probability intuitions: understanding the expected value of complex gambles 总被引:3,自引:0,他引:3
Schlottmann A 《Child development》2001,72(1):103-122
Two experiments used Information Integration Theory to study how children judge expected value of complex gambles in which alternative outcomes have different prizes. Six-year-olds, 9-year-olds and adults (N = 73 in Study 1, N = 28 in Study 2) saw chance games that involved shaking a marble in a bicolored tube. One prize was won if the marble stopped on blue, another if it stopped on yellow. Children judged how happy a puppet playing the game would be, with the prizes and probability of the blue and yellow outcomes varied factorially. Three main results appeared in both studies: First, participants in all age groups used the normatively prescribed multiplication rule for integrating probability and value of each individual outcome--a striking finding because multiplicative reasoning does not usually appear before 8 years of age in other domains. Second, all age groups based judgment of overall expected value meaningfully on both alternative outcomes, but there were individual differences--many participants deviated from the normative addition rule, showing risk seeking and risk averse patterns of judgment similar to the risk attitudes often found with adults. Third, even the youngest children took probability to be an abstract rather than physical property of the game. Overall, in contrast to the traditional view, the present results demonstrate functional understanding of probability and expected value in children as young as 5 or 6. These results contribute to the growing evidence on children's intuitive reasoning competence. This intuition can, on the one hand, support surprisingly precocious performance in young children, but it may also contribute to the biases evident in adults' judgment and decision. 相似文献