title: Learning Instance Weights in Multi-Instance Learning

authors: Foulds, James Richard

subjects: machine learning

abstract: Multi-instance (MI) learning is a variant of supervised machine learning, where each learning example contains a bag of instances instead of just a single feature vector. MI learning has applications in areas such as drug activity prediction, fruit disease management and image classification.

This thesis investigates the case where each instance has a weight value determining the level of influence that it has on its bag's class label. This is a more general assumption than most existing approaches use, and thus is more widely applicable. The challenge is to accurately estimate these weights in order to make predictions at the bag level.

An existing approach known as MILES is retroactively identified as an algorithm that uses instance weights for MI learning, and is evaluated using a variety of base learners on benchmark problems. New algorithms for learning instance weights for MI learning are also proposed and rigorously evaluated on both artificial and real-world datasets. The new algorithms are shown to achieve better root mean squared error rates than existing approaches on artificial data generated according to the algorithms' underlying assumptions. Experimental results also demonstrate that the new algorithms are competitive with existing approaches on real-world problems.

text: Learning Instance Weights in Multi-Instance Learning Multi-instance (MI) learning is a variant of supervised machine learning, where each learning example contains a bag of instances instead of just a single feature vector. MI learning has applications in areas such as drug activity prediction, fruit disease management and image classification.

This thesis investigates the case where each instance has a weight value determining the level of influence that it has on its bag's class label. This is a more general assumption than most existing approaches use, and thus is more widely applicable. The challenge is to accurately estimate these weights in order to make predictions at the bag level.

An existing approach known as MILES is retroactively identified as an algorithm that uses instance weights for MI learning, and is evaluated using a variety of base learners on benchmark problems. New algorithms for learning instance weights for MI learning are also proposed and rigorously evaluated on both artificial and real-world datasets. The new algorithms are shown to achieve better root mean squared error rates than existing approaches on artificial data generated according to the algorithms' underlying assumptions. Experimental results also demonstrate that the new algorithms are competitive with existing approaches on real-world problems.

year: 2008

title: Footprints: Participant perspectives informing pedagogy for asynchronous online discussion in initial teacher education

authors: Forbes, Dianne Leslie

subjects: online learning

abstract: This study looks at how students and staff experience asynchronous online discussion (AOD) within initial teacher education. The aim is to explore participant perspectives, including expectations of fellow participants, with a view to informing pedagogy, defined as the relationship between teaching and learning (Loughran, 2006). 

The underpinning argument is essentially that learning and teaching can be enhanced by awareness of how participants experience the situation. Understanding the complexities of AOD entails a better understanding of participants’ tacit reasoning, expectations, misunderstandings, and responses to tasks and behaviours (Brookfield & Preskill, 2005; Loughran, 2006). It is the situation as it is perceived which is central to the quality of teaching and learning, and this puts participants and their experiences at the centre of efforts to improve pedagogy and to enhance deep learning.

This study is framed by sociocultural theory and phenomenography to explore AOD through the eyes of teacher educators and teacher education students in a specific teacher education context. Participants engaged in focus groups (face-to-face and online) and a series of semi-structured interviews, generating data about experiences and perspectives of AOD. 

Key findings show the need for participants in AOD to: establish expectations for purposeful communication; to maintain a presence for learning premised on formative interaction; and to work together in ways conducive to community and student leadership in pursuit of deep learning. 

This thesis adds to the limited research literature on teacher perceptions about online teaching (Spector, 2007), and makes a contribution to addressing the neglect of student approaches to study in higher education using eLearning technologies for discussion (Ellis et al, 2008; Jackson et al, 2010; Sharpe et al, 2010). The results contribute to knowledge in the field of online learning in initial teacher education by giving rise to specific pedagogical strategies for teachers and students in given situations, and by providing conceptual tools for participants when thinking about teaching and learning through AOD. 

Participant experiences function as footprints, picking out pathways as others make their way through AOD (Salmon, 2002).

text: Footprints: Participant perspectives informing pedagogy for asynchronous online discussion in initial teacher education This study looks at how students and staff experience asynchronous online discussion (AOD) within initial teacher education. The aim is to explore participant perspectives, including expectations of fellow participants, with a view to informing pedagogy, defined as the relationship between teaching and learning (Loughran, 2006). 

The underpinning argument is essentially that learning and teaching can be enhanced by awareness of how participants experience the situation. Understanding the complexities of AOD entails a better understanding of participants’ tacit reasoning, expectations, misunderstandings, and responses to tasks and behaviours (Brookfield & Preskill, 2005; Loughran, 2006). It is the situation as it is perceived which is central to the quality of teaching and learning, and this puts participants and their experiences at the centre of efforts to improve pedagogy and to enhance deep learning.

This study is framed by sociocultural theory and phenomenography to explore AOD through the eyes of teacher educators and teacher education students in a specific teacher education context. Participants engaged in focus groups (face-to-face and online) and a series of semi-structured interviews, generating data about experiences and perspectives of AOD. 

Key findings show the need for participants in AOD to: establish expectations for purposeful communication; to maintain a presence for learning premised on formative interaction; and to work together in ways conducive to community and student leadership in pursuit of deep learning. 

This thesis adds to the limited research literature on teacher perceptions about online teaching (Spector, 2007), and makes a contribution to addressing the neglect of student approaches to study in higher education using eLearning technologies for discussion (Ellis et al, 2008; Jackson et al, 2010; Sharpe et al, 2010). The results contribute to knowledge in the field of online learning in initial teacher education by giving rise to specific pedagogical strategies for teachers and students in given situations, and by providing conceptual tools for participants when thinking about teaching and learning through AOD. 

Participant experiences function as footprints, picking out pathways as others make their way through AOD (Salmon, 2002).

year: 2012

title: An exploration of wellbeing in Hapū Wānanga through a Te Wheke framework analysis

authors: Hawaikirangi, Lena

subjects: Antenatal education

abstract: Before colonisation, Māori had comprehensive knowledge and practices around pregnancy and childbirth. With colonisation, traditional maternity knowledge and practices were replaced by western medical practices. In more recent times, antenatal education classes have played an essential role in providing information on pregnancy, birth and caring for newborns. Research reports that Māori are less likely to attend antenatal programmes and  have suggested that culturally responsive programmes may encourage better engagement by Māori. Hapū Wānanga is a kaupapa Māori antenatal education programme. No previous research has explored how whānau experience wellbeing through Hapū Wānanga. This research explores how participants experience wellbeing within the Kia Wana  Lakes Baby Service Hapū Wānanga. Three participants, including one couple, and three facilitators were interviewed. Transcripts were analysed through a framework analysis using the Te Wheke model (Pere, 1997), a comprehensive Māori model of health. Findings showed that Hapū Wānanga caters to Māori holistic views of wellbeing, as demonstrated through the Te Wheke Model (Pere, 1997). All participants reported negative experiences with mainstream antenatal services; however, whānau enjoyed their experience at Hapū Wānanga. The two dimensions that influenced participants most were whānaungatanga (kinship ties) and hā ā koro mā ā kuia mā (cultural heritage). Although whānau were empowered by their experience at Hapū Wānanga, they wanted to learn more about parenting and postpartum, mental health. Overall, my findings highlighted that culturally adapted programmes that cater to  holistic models of wellbeing could engage Māori service users in an enjoyable and empowering way. If healthcare providers are to be successful in improving indigenous peoples' wellbeing, they need to prioritise culturally adapted programmes based on holistic models of wellbeing.

text: An exploration of wellbeing in Hapū Wānanga through a Te Wheke framework analysis Before colonisation, Māori had comprehensive knowledge and practices around pregnancy and childbirth. With colonisation, traditional maternity knowledge and practices were replaced by western medical practices. In more recent times, antenatal education classes have played an essential role in providing information on pregnancy, birth and caring for newborns. Research reports that Māori are less likely to attend antenatal programmes and  have suggested that culturally responsive programmes may encourage better engagement by Māori. Hapū Wānanga is a kaupapa Māori antenatal education programme. No previous research has explored how whānau experience wellbeing through Hapū Wānanga. This research explores how participants experience wellbeing within the Kia Wana  Lakes Baby Service Hapū Wānanga. Three participants, including one couple, and three facilitators were interviewed. Transcripts were analysed through a framework analysis using the Te Wheke model (Pere, 1997), a comprehensive Māori model of health. Findings showed that Hapū Wānanga caters to Māori holistic views of wellbeing, as demonstrated through the Te Wheke Model (Pere, 1997). All participants reported negative experiences with mainstream antenatal services; however, whānau enjoyed their experience at Hapū Wānanga. The two dimensions that influenced participants most were whānaungatanga (kinship ties) and hā ā koro mā ā kuia mā (cultural heritage). Although whānau were empowered by their experience at Hapū Wānanga, they wanted to learn more about parenting and postpartum, mental health. Overall, my findings highlighted that culturally adapted programmes that cater to  holistic models of wellbeing could engage Māori service users in an enjoyable and empowering way. If healthcare providers are to be successful in improving indigenous peoples' wellbeing, they need to prioritise culturally adapted programmes based on holistic models of wellbeing.

year: 2021