MOOCs Meet Measurement Theory: A Topic-Modelling Approach

This paper adapts topic models to the psychometric testing of MOOC students based on their online forum postings. Measurement theory from education and psychology provides statistical models for quantifying a person's attainment of intangible attributes such as attitudes, abilities or intelligence. Such models infer latent skill levels by relating them to individuals' observed responses on a series of items such as quiz questions. The set of items can be used to measure a latent skill if individuals' responses on them conform to a Guttman scale. Such well-scaled items differentiate between individuals and inferred levels span the entire range from most basic to the advanced. In practice, education researchers manually devise items (quiz questions) while optimising well-scaled conformance. Due to the costly nature and expert requirements of this process, psychometric testing has found limited use in everyday teaching. We aim to develop usable measurement models for highly-instrumented MOOC delivery platforms, by using participation in automatically-extracted online forum topics as items. The challenge is to formalise the Guttman scale educational constraint and incorporate it into topic models. To favour topics that automatically conform to a Guttman scale, we introduce a novel regularisation into non-negative matrix factorisation-based topic modelling. We demonstrate the suitability of our approach with both quantitative experiments on three Coursera MOOCs, and with a qualitative survey of topic interpretability on two MOOCs by domain expert interviews.Comment: 12 pages, 9 figures; accepted into AAAI'201

Normative and Legal Pluralism: A Global Perspective

This lecture sets out to demystify the topic of legal pluralism by examining the relationship between legal pluralism, normative pluralism, and general normative theory from a global perspective. The central theme is that treating legal pluralism as a species of normative pluralism decenters the state, links legal pluralism to a rich body of literature, and helps to show that some of the central puzzlements surrounding the topic can usefully be viewed as much broader issues in the general theory of norms and legal theory. A second theme is that so-called “global legal pluralism” is in several respects qualitatively different from the older anthropological and socio-legal accounts of legal pluralism and is largely based on a different set of concerns