Family, personality, and social risk factors impacting the retention rates of first-year Hispanic and Anglo college students

This study investigated familial and behavioral differences between Hispanic and Anglo-American first-year college students. Analyses of variance and chi-square analyses were used to test for ethnic differences in (a) risk factors associated with family dysfunction, family addictions, personality factors, and social experiences, (b) student problem behaviors, namely alcohol use, drug use, and eating disorders, (c) a one-year follow-up of student retention, and (d) specific factors related to retention at the one-year follow-up. The Hispanic freshmen appeared to demonstrate resilience despite a lack of mentoring and greater paternal addiction. However, the one-year follow-up suggested that Hispanic females were at particular risk for leaving school. To improve college retention rates, social policy should focus on Hispanic students' vulnerabilities and strengths in making important developmental transitions.     

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.     

Can the Media Create Public Opinion? A Social-Identity Approach

The media remains a powerful presence in U.S. culture. It gives people news of world and local events, it entertains, and it may even function as a companion to children. Because it functions as a window to the outside world, what appears across its landscape actually may become people's reality. Thus, the potential for distorting their view of that world is high if the picture provided is unrepresentative of actual events. For example, the prevalence of violent acts on television has been linked to increased aggression and escalating impressions of a dangerous world, and the overrepresentation of youth and beauty may be a causal factor of eating disorders. In this article, we explore the possibility that the media may also serve as a powerful creator of the very public opinions it seeks to reflect in its news. Subtle nonverbal cues of newscasters have been shown to influence voting behavior, and the media's overrepresentation of the proportion of blacks in poverty may decrease whites' support of welfare. By portraying a world in which people's opinions are based on their ethnic or demographic group membership, the media may also subtly but powerfully create the very opinions they seek to reflect.     

Memory for word locations in reading

Sentences were presented in various spatial formats, and readers localised one word of each sentence using a mouse cursor directly after reading. There was a localisation advantage for cumulative over single-word displays, for left-to-right presentation over presentation in a 3 x 3 grid, and for complete over incomplete sentences. Comparing performance for predictable and unpredictable word locations suggests that word location memory in reading decays within three seconds to a span of only 2-3 entries, and that readers can then reconstruct word locations from item memory. Implications for the role of spatial cognition in reading are discussed.     

Theoretical Medicine and Bioethics Index to Volume 20

Volume Contents

heoretical Medicine and Bioethics Index to Volume 20