Using the Observer to analyze learning in virtual worlds

In this study, we describe and analyze the ways in which high school students explored a virtual solar system (VSS). VSS is a nonimmersive virtual environment that affords visual manipulations of space by altering its frame of reference. The Observer software was used to code and analyze the participants’ real-time free-exploration task. Two basic behaviors were identified across participants: establishing several home bases, and shifting between a still mode and a dynamic mode. Moreover, three overall exploration patterns emerged: thebutterfly pattern represents a superficial mode of learning; thebee pattern represents an in-depth mode of studying the various celestial objects; and theeagle pattern represents a global approach of studying the complex system. This virtual reality environment promises to provide a setting in which to further study consistent patterns and individual differences in exploration strategies.     

Visual perspective taking for avatars in a Simon task

In modern digital applications, users often interact with virtual representations of themselves or others, called avatars. We examined how these avatars and their perspectives influence stimulus–response compatibility in a Simon task. Participants responded to light/dark blue stimuli with left/right key presses in the presence of a task-irrelevant avatar. Changes in stimulus–response compatibility were used to quantify changes in the mental representation of the task and perspective taking toward this avatar. Experiments 1 and 2 showed that perspective taking for an avatar occurred in orthogonal stimulus–response mappings, causing a compatibility effect from the avatar’s point of view. In the following two experiments we introduced a larger variety of angular disparities between the participant and avatar. In Experiment 3, the Simon effect with lateralized stimulus positions remained largely unaffected by the avatar, pointing toward an absence of perspective taking. In Experiment 4, after avatar hand movements were added in order to strengthen the participants’ sense of agency over the avatar, a spatial compatibility effect from the avatar’s perspective was observed again, and hints of the selective use of perspective taking on a trial-by-trial basis were found. Overall, the results indicate that users can incorporate the perspective of an avatar into their mental representation of a situation, even when this perspective is unnecessary to complete a task, but that certain contextual requirements have to be met.     

知识图对阅读的作用研究现状述评

知识图作为辅助阅读的一种方式,其辅助作用已为大量的研究所证实。本文介绍了知识图的概念和种类及其影响因素等方面研究的基本发现和结论。但目前对知识图作用的研究还停留在对辅助作用的方式的探讨上,对机制问题的研究数量和质量上都需加强。     

Ethnic similarities and differences in the association of emotional autonomy and adolescent outcomes: comparing Euro-American and Asian-American adolescents.

This study has conducted an ethnic comparison on the strength of the association between Individuation, a subscale from the Emotional Autonomy construct presented originally by Steinberg and Silverberg in 1986, and adolescent outcomes in terms of self-esteem and susceptibility to negative peer pressure. Consistent with what was expected, the association between Individuation and lowered self-esteem was more salient among 287 Asian-American adolescent boys than among 1,353 Euro-American adolescent boys. Contrary to what was hypothesized, the association between Individuation and susceptibility to negative peer pressure was more pronounced among 1,573 Euro-American adolescent girls than among 292 Asian-American adolescent girls.     

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.     

论流行病学与医学创新

流行病学随医学的发展而发展,同时,它的发展对整个医学学科的发展也产生了重大的影响。从流行病学对医学思维、医学研究方法、医学模式及医学目的的实现等几个方面讨论了该学科在现代医学发展中的作用和地位。     

Redintegration and the Useful Lifetime of the Verbal Memory Representation

Factors affecting immediate serial recall of individual items can be classified according to whether they influence the degradation of the representation, or influence the ability to redintegrate a degraded representation. For recall of entire lists, factors can be classified according to whether or not they influence the rate at which items are recalled. We review experiments in order to classify the factors of serial position, word length, word frequency, and lexicality. We propose that the two classification systems coincide, at least for those factors whose classification is known for both schemes. We end by considering whether probability of recall of an entire list might be predicted from probability of recall of individual items.