A Markov chain is introduced to the major steps of the process of learning a subject matter by a group of students in the classroom, in order to obtain a mathematical representation of the above process. A classroom experiment for learning mathematics is also presented illustrating the applicability of our results in practice.

Basierend auf der aktuellen Studienlage wurde versucht, Modellannahmen zum auditi- ven Sprachverständnisses weiter zu ergründen. Im Mittelpunkt stand dabei die Rolle des Gyrus angularis der sprachdominanten Hemisphäre bei der semantischen Integration von Worten in einen gegebenen Satzkontext. Zu diesem Zweck wurden 15 gesunde Proban- den mithilfe von repetitiver transkranieller Magnetstimulation (rTMS) in einem Sprach- verständnisexperiment untersucht. So konnte die funktionelle Relevanz der genannten Hirnregion in Abhängigkeit der Signalqualität des gehörten Satzes und des semanti- schen Kontextes untersucht werden. Zielparameter waren dabei der Anteil der korrekt wiederholten Wörter und Schlüsselwörter des Satzes sowie die Reaktionsgeschwindigkeit.

Abductive reasoning is the process of finding a best explanation for a set of observations. In many abductive problems, like medical diagnosis, scientific discovery, debugging or troubleshooting, an amount of information far beyond the capacity limits of working memory (WM) must be processed. Although WM plays a central role in theories of human cognition, theories of abductive reasoning do not specify WM processes during the generation of explanations. On the basis of a computational model of abductive reasoning and of theories of text comprehension a mechanism is proposed that reduces WM load during abductive reasoning. The computational model views abductive reasoning as the sequential comprehension and integration of observations into a situation model that represents the current best explanation for the observations. The proposed WM mechanism assumes that the situation model is only partly kept in WM, whereas other pieces are stored in long-term memory. These long-term representation part can be reliably accessed through retrieval structures to reinstatiate information in WM during abductive reasoning. It is assumed that unexplained observations are actively maintained in WM until an explanation for them could be generated. Thereafter their representation is lost from WM. But these explained observations can be recalled from long-term memory via their integration into the situation model. This mechanism makes predictions about the availability of the mental representation of explained and unexplained observations. These predictions were tested in four experiments, using different memory tests for observations. In Experiments 1 and 2 a recognition test was used, in Experiment 3 an implicit menory test was used and in Experiment 4 the participants had to perform an unexpected recall after task interruption. The results show that unexplained observations are accessed faster than explained ones during abductive reasoning. This confirms the mechanism's assumption that unexplained observations are kept in WM and explained ones not. But explained observations seem not to be represented in long-term memory. Rather, it seems that observations are rapidly forgotten afer they are explained. Different possible reasons for this pattern of result are discussed.

No description available.

Diss. Nr. 2811 Wirtschaftswiss. St. Gallen. / Im Buchh.: Lohmar etc. : J. Eul. Literaturverz.

The dissertation topic has been selected from the field of cognitive linguistics. Research from temporal semantics, cognitive science and lexical semantics is also considered. A subset of lexical material will be analyzed in its relationship to cognitive processing and conceptualization. The special focus is on aktionsarten from a contrastive vantage point (German-English). Traditionally, the analysis of temporal phenomena in language refers to tense, temporal adverbials, temporal prepositions and conjunctions and the field of aspect and aktionsart. All mentioned categories will be sketched according to their cognitive relevance. In a contrastive discussion, differences in conceptualization between different languages can be established and systematized. The dissertation hypothesizes that aspects and their lexicalized counterparts aktionsarten can be ascribed a higher cognitive relevance than other temporal categories. / Die Thematik der Dissertation ist dem Bereich der kognitiven Linguistik entnommen und berücksichtigt Forschungen auf den Gebieten Temporalsemantik, Kognitionswissenschaft und lexikalischer Semantik. Die Menge der temporalen Kategorien einer Sprache wird definiert und ein begrenzter Ausschnitt aus dem sprachlichen Material wird im Verhältnis zu seiner kognitiven Verarbeitung und Konzeptualisierung analysiert. Die Analyse von temporalen Phänomenen in der Sprache bezieht sich gewöhnlich auf folgende Gebiete: Tempora, Temporaladverbien, temporale Präpositionen und Konjunktionen sowie Aspekt und Aktionsarten. Die Dissertation behandelt diese Gebiete (mit Ausnahme von Aspekt und Aktionsarten) überblickshaft und diskutiert ihre kognitive Relevanz. Die Aktionsarten des Verbs werden zur Analyse ausgewählt und aus einer kontrastiven Perspektive (Deutsch-Englisch) diskutiert. Die kontrastive Sichtweise ermöglicht es, in Verbindung mit interdisziplinär gewonnenen Erkenntnissen aus anderen Wissenschaftsbereichen, Unterschiede in der Konzeptualisierung in verschiedenen Sprachen zu bestimmen und zu systematisieren. Der Fokus der Dissertation liegt folglich auf einer Analyse der Aktionsarten des Verbs aus einer kognitiven Perspektive. Gleichfalls erfolgt eine Begriffsbestimmung und Abgrenzung zum Aspekt. Das temporale Ausdrucksinventar einer Sprache charakterisiert die Beziehungen von Situationen (Ereignisse, Zustände, Prozesse) zu Zeit, sowie ihre zeitliche Beziehung zu anderen Situationen. Dabei lokalisieren die Tempora die Ereignisse und Zustände, die Aktionsarten regeln die interne temporale Struktur von Situationen. Die Aspekte hingegen sind Ausdruck einer Perspektive, wie das Geschehen präsentiert wird. Die Dissertation argumentiert dafür, dass den Aspekten und ihren lexikalisierten Erscheinungsformen, den Aktionsarten, die größte kognitive Relevanz zugeschrieben werden muss.

A Markov chain is introduced to the major steps of the process of learning a subject matter by a group of students in the classroom, in order to obtain a mathematical representation of the above process. A classroom experiment for learning mathematics is also presented illustrating the applicability of our results in practice.

No description available.

Abductive reasoning is the process of finding a best explanation for a set of observations. In many abductive problems, like medical diagnosis, scientific discovery, debugging or troubleshooting, an amount of information far beyond the capacity limits of working memory (WM) must be processed. Although WM plays a central role in theories of human cognition, theories of abductive reasoning do not specify WM processes during the generation of explanations. On the basis of a computational model of abductive reasoning and of theories of text comprehension a mechanism is proposed that reduces WM load during abductive reasoning. The computational model views abductive reasoning as the sequential comprehension and integration of observations into a situation model that represents the current best explanation for the observations. The proposed WM mechanism assumes that the situation model is only partly kept in WM, whereas other pieces are stored in long-term memory. These long-term representation part can be reliably accessed through retrieval structures to reinstatiate information in WM during abductive reasoning. It is assumed that unexplained observations are actively maintained in WM until an explanation for them could be generated. Thereafter their representation is lost from WM. But these explained observations can be recalled from long-term memory via their integration into the situation model. This mechanism makes predictions about the availability of the mental representation of explained and unexplained observations. These predictions were tested in four experiments, using different memory tests for observations. In Experiments 1 and 2 a recognition test was used, in Experiment 3 an implicit menory test was used and in Experiment 4 the participants had to perform an unexpected recall after task interruption. The results show that unexplained observations are accessed faster than explained ones during abductive reasoning. This confirms the mechanism's assumption that unexplained observations are kept in WM and explained ones not. But explained observations seem not to be represented in long-term memory. Rather, it seems that observations are rapidly forgotten afer they are explained. Different possible reasons for this pattern of result are discussed.