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831.
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
832.
833.
834.
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
835.
Belva C. Collins Meada Hall Terri A. Branson Michael Holder 《Journal of Behavioral Education》1999,9(3-4):223-237
Two secondary students with moderate disabilities (one per classroom) attended Advanced English classes with peers without disabilities in a rural high school. In additional to conducting planned daily instruction, each English teacher also systematically presented three sets of information (two facts per set) to each student with disabilities during the course of the class using a parallel treatments design. Each set of information included a fact related to the English class (e.g., Begin each sentence with a capital letter.) and a fact not related to the English class (e.g., The governor of Kentucky is Paul Patton.). The special education teacher conducted daily probe sessions to document acquisition. Of the six facts presented to each student with disabilities, one student acquired two related facts and one unrelated fact, while the other student acquired two related and two unrelated facts. This investigation implies that students who are fully included can acquire information presented by the regular classroom teacher during the course of a typical class and that teachers can facilitate learning by planning to present such information in a systematic fashion. 相似文献
836.
Place MD 《Kennedy Institute of Ethics journal》1999,9(3):245-262
As the twentieth century closes, marked by triumphal strides in medical advances, the American society has yet to ensure that each person has access to affordable health care. To correct this injustice, this article calls on the nation's political and corporate leaders, providers, and faith-based groups to join all Americans in a new national conversation on systemic health care reform. The Catholic faith tradition is one that compels both a proclamation to ministry values and a commitment to speak out against the challenges or threats to what are essential to the well-being of individuals and society. The Catholic health ministry must therefore be both a voice for the voiceless and an agent of transformation. The nation's goal should be to "reposition" health care from its status as an important, but ultimately optional building block to one that is essential. 相似文献
837.
Tamsen Caruso Brown Judy Garber Michael Muto Katherine A. Schneider 《Journal of genetic counseling》1999,8(6):359-372
A client's emotional experiences and reactions to those experiences are influenced by his/her family of origin and direct or indirect interactions with various family members. Contextual therapists propose that a client's satisfaction with a relationship depends on the equity of his/her emotional interactions with family members. When relationships are inequitable, trust between individuals disintegrates. In order to reestablish trust in a relationship, a balance of interests must be restored. If not, imbalances may be passed down to future generations. A case of a woman with a family history of ovarian cancer is reviewed with the principles of contextual therapy in mind. In her family, several legacies have resulted in unbalanced relationships between family members that lead to difficulty in establishing trust within the genetic counseling session. 相似文献
838.
839.
Aimée M. Surprenant Susan L. Hura Mary P. Harper Leah H. Jamieson Glenis Long Scott M. Thede Ayasakanta Rout Tsung-Hsiang Hsueh Stephen A. Hockema Michael T. Johnson Pramila N. Srinivasan Christopher M. White J. Brandon Laflen 《Behavior research methods》1999,31(4):638-649
Ratings of familiarity and pronounceability were obtained from a random sample of 199 surnames (selected from over 80,000 entries in the Purdue University phone book) and 199 nouns (from the Ku?era-Francis, 1967, word database). The distributions of ratings for nouns versus names are substantially different: Nouns were rated as more familiar and easier to pronounce than surnames. Frequency and familiarity were more closely related in the proper name pool than the word pool, although both correlations were modest. Ratings of familiarity and pronounceability were highly related for both groups. A production experiment showed that rated pronounceability was highly related to the time taken to produce a name. These data confirm the common belief that there are differences in the statistical and distributional properties of words as compared to proper names. The value of using frequency and the ratings of familiarity and pronounceability for predicting variations in actual pronunciations of words and names are discussed. 相似文献
840.
Timothy M. Harte David L. Black Michael T. Hollinshead 《Behavior research methods》1999,31(4):680-683
This paper describes how the multi-energy sensor array has been refitted to meet the needs of measuring geomagnetic and other types of electromagnetic phenomena in an environment. This portable laptop computer system was designed to measure the interaction of multiple frequencies with the psychological and physiological processes that underlie human exposure to electromagnetic fields across the spectra. New sensors and analytical software have been implemented in the new configuration. 相似文献