title: Online estimation of discrete densities

authors: Geilke, Michael

subjects: (ensembles of) classifier chains

abstract: We address the problem of estimating a discrete joint density online, that is, the algorithm is only provided the current example and its current estimate. The proposed online estimator of discrete densities, EDDO (Estimation of Discrete Densities Online), uses classifier chains to model dependencies among features. Each classifier in the chain estimates the probability of one particular feature. Because a single chain may not provide a reliable estimate, we also consider ensembles of classifier chains and ensembles of weighted classifier chains. For all density estimators, we provide consistency proofs and propose algorithms to perform certain inference tasks. The empirical evaluation of the estimators is conducted in several experiments and on data sets of up to several million instances: We compare them to density estimates computed from Bayesian structure learners, evaluate them under the influence of noise, measure their ability to deal with concept drift, and measure the run-time performance. Our experiments demonstrate that, even though designed to work online, EDDO delivers estimators of competitive accuracy compared to batch Bayesian structure learners and batch variants of EDDO.

text: Online estimation of discrete densities We address the problem of estimating a discrete joint density online, that is, the algorithm is only provided the current example and its current estimate. The proposed online estimator of discrete densities, EDDO (Estimation of Discrete Densities Online), uses classifier chains to model dependencies among features. Each classifier in the chain estimates the probability of one particular feature. Because a single chain may not provide a reliable estimate, we also consider ensembles of classifier chains and ensembles of weighted classifier chains. For all density estimators, we provide consistency proofs and propose algorithms to perform certain inference tasks. The empirical evaluation of the estimators is conducted in several experiments and on data sets of up to several million instances: We compare them to density estimates computed from Bayesian structure learners, evaluate them under the influence of noise, measure their ability to deal with concept drift, and measure the run-time performance. Our experiments demonstrate that, even though designed to work online, EDDO delivers estimators of competitive accuracy compared to batch Bayesian structure learners and batch variants of EDDO.

year: 2013

title: Conventional, remote, virtual, and simulated work-integrated learning: A meta-analysis of existing practice

authors: Wood, Yvonne I.

subjects: COVID-19

abstract: As a result of the COVID-19 pandemic, many organizations offering work-integrated learning (WIL) opportunities were no longer able to support student placements, resulting in many institutions searching for a range of innovative solutions. Many have redesigned their conventional placement-based WIL activities or programs to enable students to meet graduate profile criteria through alternative means such as virtual or simulated WIL experiences. The literature shows there are many models of WIL beyond conventional work placements. Therefore, a meta-analysis was conducted of these WIL models, to provide a complied synthesis of existing practice from within the WIL field specifically focused on two books, the International Journal of Work-Integrated Learning, and three national WIL association conference publications. The trends and qualities that emerge from the meta-analysis of existing practice can inform the redevelopment across the different modes of conventional, remote, virtual, and simulated WIL experiences.

text: Conventional, remote, virtual, and simulated work-integrated learning: A meta-analysis of existing practice As a result of the COVID-19 pandemic, many organizations offering work-integrated learning (WIL) opportunities were no longer able to support student placements, resulting in many institutions searching for a range of innovative solutions. Many have redesigned their conventional placement-based WIL activities or programs to enable students to meet graduate profile criteria through alternative means such as virtual or simulated WIL experiences. The literature shows there are many models of WIL beyond conventional work placements. Therefore, a meta-analysis was conducted of these WIL models, to provide a complied synthesis of existing practice from within the WIL field specifically focused on two books, the International Journal of Work-Integrated Learning, and three national WIL association conference publications. The trends and qualities that emerge from the meta-analysis of existing practice can inform the redevelopment across the different modes of conventional, remote, virtual, and simulated WIL experiences.

year: 2020

title: Words on Walls: Te reo Māori (loan)words in Aotearoa New Zealand primary school classrooms

authors: Burnette, Jessie

abstract: The unique language contact situation within Aotearoa New Zealand has informed a range of studies of the defining and increasingly salient feature of New Zealand English (NZE): the integration of loanwords from the indigenous, donor language, te reo Māori, into the dominant recipient language, English (Hay et al. 2008). As NZE is experiencing a state of great lexical flux, it is important to establish which (loan)words children are regularly exposed to and what social meanings they may be acquiring in relation to these. One relevant domain that can be examined for this purpose is that of the classroom. The classroom is educational in the traditional sense, but also in the developmental sense, in the acquisition of broader social meaning. Previous schoolscape research has highlighted not only the pedagogical importance of these spaces, but their influence in the construction and transmission of language ideologies (Pzymus and Huddleston 2021; Brown 2012). The present study aims to answer two questions: RQ1) Which (loan)words are children regularly exposed to through schoolscapes in Aotearoa (and do these words align with the loanwords identified as frequently appearing in previously collected corpora)? RQ2) What implicit language ideologies does the presentation of loanwords display (e.g. are loanwords presented as ‘flagged’/foreign (Levendis and Calude 2019))? This study brings together quantitative and qualitative analysis methods in an in-depth investigation of nine classrooms within three separate primary schools, and aims to provide a broad and perationalizable framework for conducting LL.

text: Words on Walls: Te reo Māori (loan)words in Aotearoa New Zealand primary school classrooms The unique language contact situation within Aotearoa New Zealand has informed a range of studies of the defining and increasingly salient feature of New Zealand English (NZE): the integration of loanwords from the indigenous, donor language, te reo Māori, into the dominant recipient language, English (Hay et al. 2008). As NZE is experiencing a state of great lexical flux, it is important to establish which (loan)words children are regularly exposed to and what social meanings they may be acquiring in relation to these. One relevant domain that can be examined for this purpose is that of the classroom. The classroom is educational in the traditional sense, but also in the developmental sense, in the acquisition of broader social meaning. Previous schoolscape research has highlighted not only the pedagogical importance of these spaces, but their influence in the construction and transmission of language ideologies (Pzymus and Huddleston 2021; Brown 2012). The present study aims to answer two questions: RQ1) Which (loan)words are children regularly exposed to through schoolscapes in Aotearoa (and do these words align with the loanwords identified as frequently appearing in previously collected corpora)? RQ2) What implicit language ideologies does the presentation of loanwords display (e.g. are loanwords presented as ‘flagged’/foreign (Levendis and Calude 2019))? This study brings together quantitative and qualitative analysis methods in an in-depth investigation of nine classrooms within three separate primary schools, and aims to provide a broad and perationalizable framework for conducting LL.

year: 2024