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.     

Satiation, capacity, and within-session responding

Responding may change substantially over the course of a session (McSweeney, Hinson, & Cannon, 1996). The role of satiation in this effect was investigated in three experiments. Experiment 1 showed that the capacity of pigeons to consume milo over a 1-hr period was relatively stable across three different methods of measurement. In Experiment 2, pigeons were divided into two groups that differed in their capacity based on one of those measures. Key pecking was then reinforced under a variable-interval 30-s schedule with hopper durations of 2 or 5 s. According to the satiation hypothesis, subjects with small capacities should satiate faster and therefore show greater decreases in food-reinforced responding than would subjects with larger capacities. The results confirmed this prediction and showed that the magnitudes of within-session decreases were better predicted by the amount an animal consumed relative to its capacity than by absolute amount alone. In Experiment 3, each pigeon was prefed 0, 5, 15, or 25 g of milo prior to each session. Consistent with the satiation hypothesis, increases in prefeeding produced lower overall response rates in the smaller capacity subjects than in the larger capacity subjects at each level of prefeeding. These experiments demonstrate the importance of a new variable in the control of behavior, and provide a recommended technique for its measurement.     

Manipulating smoking motivation: impact on an electrophysiological index of approach motivation.

A chief goal of this research was to determine whether stimuli and events known to enhance smoking motivation also influence a physiological variable with the potential to index approach motivation. Asymmetry of electroencephalographic (EEG) activity across the frontal regions of the 2 hemispheres (left minus right hemisphere activation) was used to index approach motivation. In theory, if EEG asymmetry sensitively indexes approach dispositions, it should be influenced by manipulations known to affect smoking motivation, that is, exposure to smoking cues and tobacco deprivation. Seventy-two smokers participated in this research and were selectively exposed to a smoking-anticipation condition (cigarettes plus expectation of imminent smoking) following either 24 hr of tobacco withdrawal or ad libitum smoking. Results indicated that EEG asymmetry was increased by smoking anticipation and that smoking itself reduced EEG asymmetry. Results also suggested that smoking anticipation increased overall (bihemispheric) EEG activation. Results were interpreted in terms of major theories of drug motivation.     

Capturing Entrepreneurial Values

This research was designed to identify entrepreneurial value orientations by comparing them with the value orientations of professional managers. The SYMLOG values measuring instrument was administered in Thailand to Thai entrepreneurs ( n = 55) and Thai professional managers ( n = 200). Results show that the value orientation of the entrepreneurs differed significantly from that of professional managers on several dimensions, particularly with regard to those elements that almost always contribute to teamwork effectiveness. Implications for training and staffing are discussed.     

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.     

The Psychic Life of Fragments: Splitting from Ferenczi to Klein*

The present paper starts from the reflection that there is a curious “phenomenological gap” in psychoanalysis when it comes to processes of splitting and to describing the “life” of psychic fragments resulting from processes of splitting. In simpler terms, we are often in a position to lack a precise understanding of what is being split and how the splitting occurs. I argue that although Melanie Klein’s work is often engaged when talking of splitting (particularly through discussions on identification, projection and projective identification), there are some important phenomenological opacities in her construction. I show that by orchestrating a dialogue between Melanie Klein and Sándor Ferenczi, we arrive at a fuller and more substantive conception of psychic splitting and of the psychic life of fragments which are the result of splitting. This is even more meaningful because there are some unacknowledged genealogical connections between Ferenczian concepts and Kleinian concepts, which I here explore. While with Klein we remain in the domain of “good” and “bad” objects—polarised objects which are constantly split and projected—with Ferenczi we are able to also give an account of complicated forms of imitation producing psychic fragments and with a “dark” side of identification, which he calls “identification with the aggressor”. While attempting to take steps toward imagining a dialogue between Klein and Ferenczi, I note a certain silent “Ferenczian turn” in a late text by Melanie Klein, “On the Development of Mental Functioning”, written in 1958. In particular, I reflect on her reference to some “terrifying figures” of the psyche, which cannot be accounted for simply as the persecutory parts of the super-ego but are instead more adequately read as more enigmatic and more primitive psychic fragments, resulting from processes of splitting.