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871.
Zusammenfassung. Das hier vorgestellte Modell lernt graduell, Planungsaufgaben aus der Klasse der Maschinenbelegungsprobleme (job-shop-scheduling problems) zu lösen. Mit Hilfe des Chunking-Mechanismus von Soar wird episodisches Wissen über die Belegungsreihenfolge von Aufträgen auf Maschinen memoriert. Bei der Entwicklung des Modells wurden zahlreiche qualitative (z. B. Transfereffekte) und quantitative Befunde (z. B. Bearbeitungszeiten) aus einer früheren empirischen Untersuchung berücksichtigt. In einer Validierungsstudie wurden dieselben Aufgaben von 14 Probanden und dem Modell bearbeitet. Die Passung von Simulationsdaten und empirischen Ergebnissen fiel insgesamt gut aus. Allerdings löst das Modell die Aufgaben schneller und zeigt auch einen etwas besseren Lernverlauf als die Probanden. Das Modell liefert eine Erklärung für das Rauschen, das typischerweise bei Bearbeitungszeiten zu beobachten ist: es handelt sich um erworbenes Wissen, das mehr oder weniger gut und auch unterschiedlich häufig auf neue Situationen übertragen wird. Der Lernverlauf der Probanden entspricht nur für aggregierte Daten einer Potenzfunktion (power law). Der vorgestellte Mechanismus zeigt, wie ein symbolisches Modell der Informationsverarbeitung graduelle Verhaltensänderungen generiert und wie der offensichtliche Erwerb allgemeiner Prozeduren ohne explizites Lernen von deklarativen Regeln erfolgen kann. Es wird nahegelegt, daß es sich hier um die Modellierung einer Form impliziten Lernens handelt. Summary. The model presented here gradually learns how to perform a job-shop scheduling task. It uses Soar's chunking mechanism to acquire episodic memories about the order to schedule jobs. The model was based on many qualitative (e.g., transfer effects) and quantitative (e.g., solution time) regularities found in previously collected data. The model was tested with new data where scheduling tasks were given to the model and to 14 subjects. The model generally fit these data with the restrictions that the model performs the task (in simulated time) faster than the subjects, and its performance improves somewhat more quickly than the subjects' performance. The model provides an explanation of the noise typically found in problem solving times - it is the result of learning actual pieces of knowledge that transfer more or less to new situations but rarely by an average amount. Only when the data are averaged (i.e., over subjects) does the smooth power law appear. This mechanism demonstrates how symbolic models can exhibit a gradual change in behavior and how the apparent acquisition of general procedures can be performed without resorting to explicit declarative rule generation. We suggest that this may represent a type of implicit learning. 相似文献
872.
873.
874.
Luc Steels 《Kognitionswissenschaft》1999,8(4):143-150
Linguistics must again concentrate on the evolutionary nature of language, so that language models are more realistic with respect to human natural languages and have a greater explanatory force. Multi-agent systems are proposed as a possible route to develop such evolutionary models and an example is given of a concrete experiment in the origins and evolution of word-meaning based on a multi-agent approach. 相似文献
875.
Robert Cohen Shirley Wiley Donald P. Oswald Kathi B. Eakin Al M. Best 《Journal of child and family studies》1999,8(4):463-476
The Comprehensive Services Act for At Risk Youth and Families of Virginia (CSA), is a service, funding, and organizational reform initiative designed to improve the provision of child centered and family focused services within a community setting. We conducted this study in order to assess the feasibility of applying utilization management principles to the CSA in order to improve the appropriateness, quality, and cost effectiveness of this service delivery system. Data were gathered through focus groups, surveys, clinical profiling, and analysis of costs, and service utilization. While overall program costs increased since inception of the program, the costs per child served rose less than the rate of inflation. CSA appeared to be serving children with a high degree of emotional and behavioral difficulties. There was considerable variation among localities in placement patterns. A majority of survey and focus group respondents were willing to consider the application of utilization management principles to the CSA as long as decision making remained within localities. We concluded that there is a constructive role for utilization management approaches to improve the appropriateness and quality of services as well as enhancing efficiency in child mental health. 相似文献
876.
This work evaluated the prospect that organizational accounts of the retention of list information by monkeys might be an
artifact of familiarity with conditional relationships. Seven sophisticated macaques were trained on four five-item lists.
Each acquisition selectively excluded one of the internal conditional pairs of the typical four-problem sequence (AB,BC,CD,DE)
that defines a five-item serially ordered list. Then, all possible novel pairings and the trained pairs appeared together
in a test. After this, the previously omitted pair was trained and animals were retested. On all tasks, initial tests revealed
little organization and much intersubject variability of characteristic choice strategies, but subsequent inclusion of all
four conditional pairs always yielded organized serial choice. On both the four-problem tests and in a later retention, errors
were directly related to interitem distance between the objects paired on test trials. These results helped to specify the
conditions required for demonstration of non-human primate analogs of transitivity, and showed that even sophisticated monkeys
organize information in retention only if they know all interitem relationships.
Received: 7 October 1998 / Accepted after revision: 10 October 1999 相似文献
877.
878.
International Journal for Philosophy of Religion - 相似文献
879.
This study explores whether alternating betweenthe pronouns he and she ina text is an effective way to avoid sexist language.Participants were psychology students at a largemidwestern university and were predominately White and frommiddle-class backgrounds. Students read two versions ofan essay, one that alternated between masculine andfeminine pronouns and one that exclusively used paired, he or she-type pronouns. Readersperceived the alternating version to be biased in favorof females and lower in overall quality than the pairedversion. However, the alternating version appeared to be more effective at combating sexism,suggesting an alternating strategy may be desirable forauthors with this goal. If the author is not primarilyconcerned with increasing readers' awareness of gender issues, techniques such as pluralization or thesingular they may be moreappropriate. 相似文献
880.