Educational Expectations and School Achievement of Urban African American Children

The mechanisms used to convey parents' and teachers' educational expectations for the academic achievement of low-income African American children were explored using data from the Chicago Longitudinal Study. A total of 712 children were studied. A model of mediated effects was used to test the processes of influence from parents' and teachers' expectations to sixth-grade outcomes. Children's perceptions of expectations were hypothesized to mediate the effect of expectations to school outcomes. Study findings revealed that these perceptions only partially mediated the effects of expectations to sixth-grade reading and math outcomes, yet added unique independent variance to these outcomes. Prior achievement emerged as a powerful mediator of the effects of early educational intervention and sociodemographic variables to sixth-grade outcomes. These findings suggest a need to further investigate the processes of communicating parent and teacher expectations.     

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.     

A grouping interpretation of the modality effect in immediate probed recognition

In a series of experiments on immediate probed recognition for eight 3-digit numbers, it was shown that if the target modality involved auditory components and the effect of the similarity of the modality of the probe to that of the targets was controlled, unequivocal evidence was obtained for an auditory superiority effect (modality effect) for hit rates for the final items of the list. Moreover, false-alarm rates were significantly lower following targets with an auditory component than they were following silently seen targets. It is argued that this pattern of hits and false alarms is consistent with the idea that targets that have an auditory component yield memory representations that are better grouped as units than are those for targets that are only silently seen; in particular, if a new probe has a first digit that accidentally matches the first digit of a target item, it is more likely that the subject will mistakenly identify this new probe as old (give a false alarm) if the target has only been partially encoded because it was only silently seen.     

Semantic Contribution to Immediate Serial Recall Using an Unlimited Set of Items: Evidence for a Multi-level Capacity View of Short-term Memory

The purpose of this study was to assess the respective roles of lexical and semantic levels of representations in immediate serial recall, by testing participants with items that varied on both these dimensions. Contrary to most studies where a small fixed set of words are repeated over trials, the current items were tested once by sampling them from an unlimited set of items without replacement. Participants recalled three classes of words under articulatory suppression: nonwords, function words, and content words. Results indicated an advantage for function words over nonwords, confirming a specifically lexical contribution to immediate serial recall. Additionally, content words were more frequently recalled than function words, confirming a semantic contribution. These results imply that non-phonological factors influence immediate serial recall and are consistent with a multi-level capacity view of short-term memory.     

When Interviewers Desire Accurate Impressions: The Effects of Notetaking on the Influence of Expectations1

The present study explored the possibility that notetaking would help accuracy-minded interviewers to avoid cognitive expectation biases. Interviewers in simulated employment interviews were given bogus pre-interview expectations about their applicants and were either encouraged or not encouraged to take extensive notes. Consistent with past research on accuracy-motivated interviewers, both notetaking and non-notetaking interviewers avoided creating self-fulfilling prophecies. Of central interest, notetaking reduced the cognitive biasing effect of negative expectations on interviewers' overall impressions of their applicants, but failed to reduce cognitive bias in interviewers' evaluations of expectation-specific applicant characteristics. In conjunction with the motivation to form accurate impressions, notetaking can help to reduce the impact of erroneous pre-interview expectations in interviewer final evaluations.