title: Applying machine learning to subject classification and subject description for information retrieval

authors: Cunningham, Sally Jo

subjects: computer science

abstract: This paper describes an experiment in applying standard supervised machine learning algorithms (C4.5 and Induct) to the problem of developing subject classification rules for documents. These algorithms are found to produce surprisingly concise models of document classifications. While the models are highly accurate on the training sets, evaluation over test sets or through cross-validation shows a significant decrease in classification accuracy. Given the difficult nature of the experimental task, however, the results of this investigation are promising and merit further study. An additional algorithm, 1R, is shown to be highly effective in generating lists of candidate terms for subject descriptions.

text: Applying machine learning to subject classification and subject description for information retrieval This paper describes an experiment in applying standard supervised machine learning algorithms (C4.5 and Induct) to the problem of developing subject classification rules for documents. These algorithms are found to produce surprisingly concise models of document classifications. While the models are highly accurate on the training sets, evaluation over test sets or through cross-validation shows a significant decrease in classification accuracy. Given the difficult nature of the experimental task, however, the results of this investigation are promising and merit further study. An additional algorithm, 1R, is shown to be highly effective in generating lists of candidate terms for subject descriptions.

year: 1995-06

title: Algebraic invariants arising from the chromatic polynomials of theta graphs

authors: Delbourgo, Daniel

abstract: This paper investigates some algebraic properties of the chromatic polynomials of theta graphs, i.e. graphs which have three internally disjoint paths sharing the same two distinct end vertices. We give a complete description of the Galois group, discriminant and ramification indices for the chromatic polynomials of theta graphs with three consecutive path lengths. We then do the same for theta graphs with three paths of the same length, by comparing them algebraically to the first family. This algebraic link extends naturally to generalised theta graphs with k + 1 branches.

text: Algebraic invariants arising from the chromatic polynomials of theta graphs This paper investigates some algebraic properties of the chromatic polynomials of theta graphs, i.e. graphs which have three internally disjoint paths sharing the same two distinct end vertices. We give a complete description of the Galois group, discriminant and ramification indices for the chromatic polynomials of theta graphs with three consecutive path lengths. We then do the same for theta graphs with three paths of the same length, by comparing them algebraically to the first family. This algebraic link extends naturally to generalised theta graphs with k + 1 branches.

year: 2014

title: Intersecting knowledge worlds: Describing the cultural interfaces within a socioscientific issue

authors: Wagner, Brent

subjects: cultural interface

abstract: Increasing numbers of science teachers in Aotearoa New Zealand are exploring ways to incorporate indigenous mātauranga Māori (Māori knowledge and ways of knowing) into their science programmes. This article presents findings from a study that examined how senior biology students in two English-medium secondary schools incorporated mātauranga Māori alongside biological science knowledge in their discussions about the use of 1080 poison to control mammalian predators. From a social constructivist ontology and interpretivist mode of inquiry using qualitative methodology, a triadic epistemic agency conceptual framework was developed inductively and used to analyse students’ written scripts for their national school leaving qualification (NCEA), and transcriptions of individual interviews. The study took place prior to the introduction of equal status to mātauranga Māori within the New Zealand Curriculum. Deductive analysis using the Triadic identified a group of ten students who drew from both knowledge systems, with varying degrees of knowledge integration. In addition to detailed representations of the theoretical space of the locale of the learner, the findings also identified three distinctive cultural interfaces occupied by the students: conflicted, parallel, and, connected. The findings underscore the importance of enabling diverse knowledge systems in biology classes to converge. Specifically, the incorporation of mātauranga Māori alongside biological science knowledge encourages a critical stance towards knowledge claims, supports pluralist knowledge use among culturally and linguistically diverse learners and promotes critical engagement with socioscientific issues (SSI) in senior secondary school biology.

text: Intersecting knowledge worlds: Describing the cultural interfaces within a socioscientific issue Increasing numbers of science teachers in Aotearoa New Zealand are exploring ways to incorporate indigenous mātauranga Māori (Māori knowledge and ways of knowing) into their science programmes. This article presents findings from a study that examined how senior biology students in two English-medium secondary schools incorporated mātauranga Māori alongside biological science knowledge in their discussions about the use of 1080 poison to control mammalian predators. From a social constructivist ontology and interpretivist mode of inquiry using qualitative methodology, a triadic epistemic agency conceptual framework was developed inductively and used to analyse students’ written scripts for their national school leaving qualification (NCEA), and transcriptions of individual interviews. The study took place prior to the introduction of equal status to mātauranga Māori within the New Zealand Curriculum. Deductive analysis using the Triadic identified a group of ten students who drew from both knowledge systems, with varying degrees of knowledge integration. In addition to detailed representations of the theoretical space of the locale of the learner, the findings also identified three distinctive cultural interfaces occupied by the students: conflicted, parallel, and, connected. The findings underscore the importance of enabling diverse knowledge systems in biology classes to converge. Specifically, the incorporation of mātauranga Māori alongside biological science knowledge encourages a critical stance towards knowledge claims, supports pluralist knowledge use among culturally and linguistically diverse learners and promotes critical engagement with socioscientific issues (SSI) in senior secondary school biology.

year: 2026