Within educational data mining, many statistical models capture the learning of students working individually. However, not much work has been done to extend these statistical models of individual learning to a collaborative setting, despite the effectiveness of collaborative learning activities. We extend a widely used model (the additive factors…

Background: Developing sufficient mathematical skills is a prerequisite to function adequately in society today. Given this, an important task is to increase our understanding regarding the cognitive mechanisms underlying young people's acquisition of early number skills and formal mathematical knowledge. Aims: The purpose was to examine whether…

Combinatorial scientific computing plays an important enabling role in computational science, particularly in high performance scientific computing. In this thesis, we will describe our work on optimizing matrix-vector multiplication using combinatorial techniques. Our research has focused on two different problems in combinatorial scientific…

Poses questions concerning methods of using specificity information in a weighting scheme. (JB)

The model assumes that the relevance assigned to a document by a juror is a random variable. (PF)

Presents notations and definitions necessary to identify the concepts and relationships that are important in modelling information retrieval objects and processes in the context of vector spaces. Earlier work on the use of vector models is evaluated in terms of the concepts introduced and certain problems are identified. (Author/EM)

A model for an information retrieval system in which recall and precision are inversely related is described, and then the anomaly is resolved. (PF)

A model is proposed to explain the retrieval characteristics of an information retrieval system. (Author)

Explores the properties of independent variables in information retrieval systems and defines a class of basic variables named M-factors. (Author/PF)

Suggests that a possible reason for receiver-operating characteristics (ROC) curves having a slope other than unity when plotted on Normal-deviate axes is that the dichotomy into relevant and nonrelevant items is artificial, and that there is really a bivariate distribution of objective relevance and relevance as assessed by the information…

The theory of fuzzy sets is used to provide a rigorous formulation of the problem of associative retrieval. This formulation suggests the idea of using fuzzy clustering to organize data for retrieval. (Author)

The derivation of a general retrieval effectiveness measure is investigated. Inconsistencies in the definition of relative importance are resolved, and it is shown that the influence of the assigned weight on the effectiveness measure can produce counterintuitive results. An alternative effectiveness measure provided by the Marczewski-Steinhaus…

Proposes an alternative methodology for handling queries with weighted search terms or search criteria in a fuzzy environment as a means of improving the performance of information retrieval systems. (EM)

Analyzes the nature of Boolean information retrieval in relation to the discrete weights of query terms, examines assigned weights from an approach involving thresholds, and generates an evaluation mechanism which allows the user to attach a threshold to the query term. Thirteen references are listed. (FM)

Defines a fuzzy retrieval model as the basis for extending a weighted Boolean information retrieval system in which numeric query weights are replaced by linguistic descriptors that specify the degree of importance of the terms. A relevance classification process is described, and implementation and evaluation of the fuzzy retrieval model is…