Knowledge level learning and the power law: A soar model of skill acquisition in scheduling

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.     

The puzzle of language evolution

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.     

The Effect of Inhibition of Return on Lexical Access

Abstract—Inhibition of return refers to a bias against returning attention to a location or object that has been recently attended. Recent research has shown that inhibition of return can be found not only in simple detection tasks, but also in tasks requiring relatively simple discrimination judgments. The present experiments examined whether inhibition of return occurs in tasks that require complex discriminations such as lexical decision and categorization tasks. Not only was inhibition of return found in both experiments, but a greater amount of inhibition was found for low-frequency words than for high-frequency words. These findings suggest that inhibition of return not only inhibits returning attention to previously attended locations, but can also affect the processing that is required for lexical access.     

Predictors of therapeutic response to treatments for depression: a review of electrophysiologic and dichotic listening studies

There are few clinical or biologic predictors of response to treatments for depression. This article reviews growing evidence that electrophysiologic and neurocognitive measures of brain function may be of value as predictors of therapeutic response to antidepressants. Initial studies using dichotic listening, quantitative electroencephalography, or event-related brain potential measures have found differences between treatment responsive and nonresponsive subgroups of depressed patients. The neurophysiologic basis for these differences and the potential clinical utility of electrophysiologic and dichotic predictors of treatment outcome remain to be determined in future studies.     

Do tricyclic responders have different brain laterality?

A previous study showed that depressed patients who improved with tricyclic antidepressant medication had dichotic complex tones test results suggesting right-hemisphere dysfunction relative to nonresponders and controls (G. E. Bruder et al., 1990). A new sample of 68 depressed patients completed dichotic consonant-vowel (CV) and complex tones (CT) tests and then were treated with imipramine or placebo. A significant Ear x Test x Treatment x Response interaction was accounted for by significantly poorer left-ear accuracy for CVs among imipramine responders compared with nonresponders, placebo responders, and controls. CV left-ear accuracy was also significantly greater among placebo responders than placebo nonresponders and controls. The results only partially replicate the prior study in that evidence of right-hemisphere dysfunction in tricyclic responders was seen for the CV test but not the CT test.     

The assessment of obsessionality using the Padua inventory: its validity in a British non-clinical sample

The Padua Inventory (PI) is a measure of obsessive–compulsive phenomena, which permits measurement of both number and severity of symptoms. Data is available from Italy, the US, the Netherlands and Australia on non-clinical samples. The present study provides a psychometric evaluation of the PI on a British non-clinical sample (N=1855). Comparisons are made with other data and further suggestions for the use of the PI are made. Results from the present study indicate that the PI has similar, though not identical, factor structure to previous studies, adequate internal reliability and construct validity. Four factors emerged, containing clusters of items broadly relating to ‘impaired control over mental activities/doubting', ‘contamination', ‘checking' and ‘worries about losing control over motor behaviour' and these included most of the items loading on the same factors in earlier studies together with additional items.The relationships of age and gender with the PI scores are investigated. Differences were found from the Sanavio (1988) [Sanavio, E. (1988). Obsessions and compulsions: the Padua Inventory. Behaviour Research and Therapy, 26, 169–177.] Italian sample. These differences are in keeping with other available data from British samples and other data on the epidemiology of Obsessive Compulsive Disorder. The five factor structure found in the one study using clinical and non-clinical subjects is discussed in relation to the present analyses.     

Authority,Psychotherapy and the Authority of the Therapist in the Religious Haredi Community

This article considers the meaning and significance of authority, and its relevance to the transference process, within the framework of psychotherapy in the orthodox Jewish (Haredi) community in Israel. In this community, deeply-rooted habits of obedience to the commandments of the Torah and the authority of the Rabbi are integral to maintaining an orthodox way of life. Clinical vignettes with Haredi patients are presented to illustrate the complexities that arise when both patient and therapist belong to the orthodox community, and highlight the authority-related issues that are central to the therapy. This combination of factors requires a sensitive and finely-tuned approach which will enable the therapist to maintain the treatment framework while still accommodating the orthodox way of life.     

Melancholic Response to War Destruction and the Emergence of a Group Assumption of Post-Ness

What psychological response does war and forced displacement evoke in victims? How do survivors of war communicate their experiences to their children? Finally, what culture does the psychological response to loss shape? Using data collected through interviews, psychological consultations, and children’s drawings from two sources—the ongoing Syrian civil war and the Bosnian war of 1992–1995, this paper suggests that the experience of the war generation becomes the organizing axis of their identity and that of their children. It seeks to demonstrate that survivor parents communicate their experience of loss through gesture, act, and object rather than through a coherent narrative. Whereas survivor children use metaphoric and metonymic readings of their parents’ everyday performance in order to construct meaning and form their identities as descendants of a given family. This paper argues that such an identity is characterized by ambivalence towards the self and towards others, melancholic longing for an idealized pre-war past, and the impossibility of letting it go.