This thesis is about "authentic learning": learning from life-like contexts. The construct derived from the social situated approach (Lave & Wenger, 1991), has surprisingly no counterpart in cognitive psychology. The first objective of this thesis is to develop a cognitive formulation of authentic learning from classical cognitive works and recent neuroscience studies findings. The characteristically cognitive feature posited is "n-coding", the encoding of multimodal input (verbal, visual, kinesthetic, social...). To test quasi-experimentally the effectiveness of this cognitive definition, a review of the instructional literature identified Collaborative Group Problem Solving (Heller et al., 1992) as an appropriate candidate for authentic instruction in physics. / The study design was comprised of one control and three treatment conditions varying in degrees of n-coding: (high, medium and low) while controlling for each treatment group's "participatory framework". All students were assessed before and after instruction on the FCI (Hestenes et al., 1992). Confidence levels were measured with each FCI question resulting in four new measures (gain in mean: confidence, right answer confidence, wrong answer confidence and weighted FCI). Procedural problem solving skills were measured through final exam grades. / Two empirical questions are posed. First, does increasing n-coding enhance learning? Second, since cognitive n-coding is unaccountable from the social perspective, does the situated perspective "subsume" the cognitive (Greeno, 1998)? Here, a quasi-experiment was not only used to test interventions but paradigm effectiveness, a methodological first. / Results shows that high and medium n-coding groups were significantly more effective than the situated low n-coding group (p=0.003) showing the effectiveness of increasing n-coding and refuting the claim that social approaches must subsume cognitive ones. No significant difference was found between high and medium n-coding groups (p=0.74) whereas all treatment groups differed from the control (p=0.0497), replicating findings on the effectiveness of non-traditional instruction (Hake, 1998). / Competing cognitive and social perspectives (Schoenfeld, 1999) may be better replaced by cross-paradigm symbioses such as importing authentic learning from situated approach into cognition. A model for reflecting on cross-scale symbioses is developed through the presence of self-similar patterns across scales (from micro-cognitive to macro-social). The fractal is put forward as a metaphor for the field of education and may serve to unify paradigms and yield optimal pictures of learning.

No description available.

This thesis is concerned with two-dimensional models that are integrable in the presence of a boundary and whose spectrum in the bulk is constituted of massless particles. Although there is already a vast literature on the subject (e.g. Kondo and Callan-Rubakov models), the common minimal denominator in all these situations is the fact that the bulk theory is conformal invariant and it is the boundary that is responsible for the broken scale invariance. Here, our purpose is to consider the alternative situation, where the boundary respects the conformal invariance of the theory and the renormalization group trajectory is controlled by a bulk perturbation. The model in question is the principal chiral model at level k = 1. We propose the set of permissible boundary conditions suggested by the symmetries of the problem and compute the corresponding minimal reflection matrices. For one of the boundary conditions we compute the boundary ground state energy and the boundary entropy using the technique of boundary thermodynamic Bethe ansatz. In the infrared limit our results are shown to be in complete agreement with the predictions of the boundary conformal field theory approach. Finally, we consider the classical supersymmetric Liouville theory on the half-line and compute the boundary conditions compatible with the superconformal invariance. We construct an infinite set of commuting integrals of motion using Lax-pair techniques and discuss some aspects of the quantum theory as well as its relation to the super Korteweg-de Vries equation.

No description available.

The rate at which individuals acquire new cognitive skills may vary quite substantially, some acquiring a new skill more rapidly and efficiently than others. It has been shown through the analysis of think aloud protocols that learning performance on a map learning task, for instance, is associated with the use of certain learning procedures. In the domain of mathematical problem solving, it has also been shown that performance is associated with strategic as opposed to tactical decision making. Previous research on learning and problem solving has tended to focus on tactical processes, ignoring the role of strategic processes in learning and problem solving. There is clearly a need to examine the role of strategic processes in learning and to determine whether they might be an important source of individual differences in learning performance. A related question concerns teaching thinking skills. If it is possible to determine those learning procedures that differentiate good from poor learners, is it then possible to teach the effective procedures to a group of novice students in order to enhance the rate of skill acquisition? Results from the experiments reported here show that novices differ, and that learning performance is related to the use of certain learning procedures, as revealed by subjects' think aloud protocols. A follow-up study showed that novices taught to use the procedures differentiating good from poor learners performed at a higher level than two control groups of novices. A coding scheme was developed to explicitly examine learning at macroscopic and microscopic levels, and to contrast tactical with strategic processes. Discriminant function analysis was used to examine differences between good and poor learners. It was shown that good learners more frequently use executive processes in learning episodes. A study of the same subjects learning to use statistical packages on a microcomputer corroborate these findings. Thus, results extend those obtained from the first study. A study of the knowledge structures possessed by novices was complicated by differences in levels of statistical knowledge. Multidimensional scaling techniques revealed differences between novices with three statistical courses behind them, but not among those with only two statistical courses behind them. Among those novices with three statistical courses behind them, faster learners' knowledge structures more closely resembled those of experienced users of statistical packages than did those of slower learners.

Object play is widely considered a primary medium through which children develop cognitive skills. In an attempt to examine the relative importance of different types of play experience and selected play components on children's subsequent approach to problem solving, 31 four-year-olds (19 boys, 12 girls) were matched on sex and PPVT-R raw score, and were then assigned to one of the three treatment groups. Seven triplets (5 male, 2 female) and five pairs (2 male, 3 female) of children were formed. Children in each group were exposed to a different type of experience relative to task-relevant materials (active play, passive observation of play, and no involvement) and subsequently given a lure-retrieval task. The solution to this task involved the joining of the two longest sticks with a block to produce a tool to retrieve a lure. Subjects were compared on their problem-solving performance as measured by solution time and specific object play components obtained in Cheyne and Rubin's (1983) study were replicated in this study. Examination of additional components in play indicated that problem solution was enhanced not only by frequent use of long double-stick construction, but also by double-stick constructions with any stick length. Problem-solving performance of the three groups of children were not significantly different. However, a Treatment x Sex interaction was noted among children in the active and passive groups; passive girls spent more time and tended to require more assistance to task solution than active girls, active boys, and passive boys. Factors which may have contributed to this finding are discussed.

This experiment was designed to compare the before and after ratings of solutions generated by individuals using two problem solving scaffolds, brainstorming and the hierarchical technique. Participants were randomly assigned to one of eight conditions which varied by type of scaffold (procedures to guide thinking), type of tool used to assist solution generation (random word list or thesaurus), and type of technology utilized (computer versus paper and pencil). Using a personal problem, participants generated solutions on paper until they could no longer add to their list. Then participants were taught to use a scaffold, either brainstorming or the hierarchical technique , and allowed to continue generating solutions either on paper or on a computer with one of two tools to stimulate ideas, a random word list or a thesaurus.Results indicated that participants trained on brainstorming generated solutions that were more original than participants trained on the hierarchical technique. The mean number of solutions generated was highest when participants used the computer recording tool paired with a thesaurus. Finally, participants rated solutions higher on practicality when they used a random word list instead of a thesaurus. / Department of Psychological Science

There is no abstract available for this dissertation.

The present study sought to investigate the personality characteristics of oppositional children, using the subscales of the Personality Inventory for Children (PIC) to plot a personality profile of oppositional children. Twelve of the 16 subscales were selected for inclusion in the study. Selection criteria were based upon how closely the items that made up each scale reflected aspects of the oppositional child's personality or environment, as described in related literature.A research design was developed that compared oppositional children to non-oppositional children. Oppositional type was determined by an interview with the parent who filled out the PIC on behalf of their child. The PICs were scored; the profiles were plotted and compared to an anticipated profile of oppositional children, using expected T score elevations.The data from this study were analyzed using multivariate and univariate statistics. The .05 level of significance was established as the critical probability level.Findings1) No significant interaction existed between the sex and oppositionaltype (oppositional or non-oppositional) of the child.2) Oppositional children were found to differ significantly on the 12subscales selected for inclusion in the study.3) Oppositional children were significantly higher on 11 of the 12subscales and significantly lower on one of them.ConclusionsA personality profile of oppositional children does exist on selected scales of the PIC. Oppositional children's personality characteristics can be described using these scales.On the basis of the findings, conclusions were drawn and speculations were made concerning the utilization of the PIC to describe personality characteristics of oppositional children and for the prediction of oppositional children's PIC profiles.

The purpose of this experiment was to explore the relationship between the "Big Five" personality dimensions, training and problem-solving effectiveness. The second purpose of this study was to explore the effects of training upon the quantity and self-reported quality of solutions generated to ill-structured problems. Subjects generated solutions to a problem and then were trained in either brainstorming or the hierarchical method. Then they were asked to generate additional solutions and rate their solutions. Subjects returned after a month and completed the NEO-FFI and then generated solutions to a different problem. Subjects in the hierarchical condition produced more solutions than those using brainstorming. Subjects in the hierarchical condition also rated their solutions higher on a subjective quality measure. Unexpectedly, the extroversion /introversion personality dimension was not related to overall quantity or quality. There were several personality-training interactions on the quantity and quality measures. / Department of Psychological Science