Bayesian algorithms with applications

Advances in algorithms for approximate sampling from a multivariable target function have led to solutions to challenging statistical inference problems that would otherwise not be considered by the applied scientist. Such sampling algorithms are particularly relevant to Bayesian statistics, since the target function is the posterior distribution of the unobservables given the observables. In this thesis we develop, adapt and apply Bayesian algorithms, whilst addressing substantive applied problems in biology and medicine as well as other applications. For an increasing number of high-impact research problems, the primary models of interest are often sufficiently complex that the likelihood function is computationally intractable. Rather than discard these models in favour of inferior alternatives, a class of Bayesian "likelihoodfree" techniques (often termed approximate Bayesian computation (ABC)) has emerged in the last few years, which avoids direct likelihood computation through repeated sampling of data from the model and comparing observed and simulated summary statistics. In Part I of this thesis we utilise sequential Monte Carlo (SMC) methodology to develop new algorithms for ABC that are more efficient in terms of the number of model simulations required and are almost black-box since very little algorithmic tuning is required. In addition, we address the issue of deriving appropriate summary statistics to use within ABC via a goodness-of-fit statistic and indirect inference. Another important problem in statistics is the design of experiments. That is, how one should select the values of the controllable variables in order to achieve some design goal. The presences of parameter and/or model uncertainty are computational obstacles when designing experiments but can lead to inefficient designs if not accounted for correctly. The Bayesian framework accommodates such uncertainties in a coherent way. If the amount of uncertainty is substantial, it can be of interest to perform adaptive designs in order to accrue information to make better decisions about future design points. This is of particular interest if the data can be collected sequentially. In a sense, the current posterior distribution becomes the new prior distribution for the next design decision. Part II of this thesis creates new algorithms for Bayesian sequential design to accommodate parameter and model uncertainty using SMC. The algorithms are substantially faster than previous approaches allowing the simulation properties of various design utilities to be investigated in a more timely manner. Furthermore the approach offers convenient estimation of Bayesian utilities and other quantities that are particularly relevant in the presence of model uncertainty. Finally, Part III of this thesis tackles a substantive medical problem. A neurological disorder known as motor neuron disease (MND) progressively causes motor neurons to no longer have the ability to innervate the muscle fibres, causing the muscles to eventually waste away. When this occurs the motor unit effectively ‘dies’. There is no cure for MND, and fatality often results from a lack of muscle strength to breathe. The prognosis for many forms of MND (particularly amyotrophic lateral sclerosis (ALS)) is particularly poor, with patients usually only surviving a small number of years after the initial onset of disease. Measuring the progress of diseases of the motor units, such as ALS, is a challenge for clinical neurologists. Motor unit number estimation (MUNE) is an attempt to directly assess underlying motor unit loss rather than indirect techniques such as muscle strength assessment, which generally is unable to detect progressions due to the body’s natural attempts at compensation. Part III of this thesis builds upon a previous Bayesian technique, which develops a sophisticated statistical model that takes into account physiological information about motor unit activation and various sources of uncertainties. More specifically, we develop a more reliable MUNE method by applying marginalisation over latent variables in order to improve the performance of a previously developed reversible jump Markov chain Monte Carlo sampler. We make other subtle changes to the model and algorithm to improve the robustness of the approach.

Towards a typology of structural arrangements for shared services : evidence from the higher education sector

Shared services are increasingly prevalent in practice, their introduction potentially entailing substantive and highly consequential organizational redesign. Yet, attention to the structural arrangements of shared services has been limited. This study explores types of structural arrangements for shared services that are observed in practice, and the salient dimensions along which those types can be usefully differentiated. Through inductive attention to the shared services literature, and content analysis of 36 secondary case studies of shared services in the higher education sector, three salient dimensions emerged: (1) the existence or not of a separate organizational entity, (2) an intra- or inter-organizational sharing boundary, and (3) involvement or not of a third party. Each dimension being dichotomous yields 23 combinations, or eight shared services structural arrangement types. Each of the eight structural arrangement types is defined and demonstrated through case examples. The typology offers clarity around shared services structural arrangements. It can serve as a useful analytical tool for researchers investigating the phenomenon further, and for practitioners considering the introduction or further development of shared services arrangements. Important follow on research is suggested too.

Well-being of refugees from Burma: a salutogenic perspective

A salutogenic approach explored themes of strength and well-being in life stories of Burmese refugees (N = 18) in Australia. Previous refugee studies have tended to focus on negative responses to traumatic events (e.g. posttraumatic stress disorder, depression). To widen the scope of refugee related research the focus of the current study was informed by a salutogenic perspective, exploring sources of strength that may facilitate well-being. Semi-structured narrative interviews explored: the participant's life before fleeing Burma, the journey of exile, and post-migration in Australia. Eight women and 10 men (Mage = 39 years) were interviewed and transcriptions analysis of narratives was conducted using Interpretative Phenomenological Analysis (IPA), with major themes being explicated. Super-ordinate themes pertaining to strength during times of hardship were identified and explicated as: support from interpersonal relationships, the pivotal role of values, a sense of future and agency, and reliance on spiritual or religious beliefs. Results indicate the existence of sources of strength that may contribute to human responses in times of hardship. Recognition and reflection of strengths may be incorporated into therapeutic and resettlement approaches for people from refugee backgrounds.

Civil procedure : Commentary and materials

This book provides a comprehensive analysis of the practical and theoretical issues encountered in Australian civil procedure. Each chapter features in-depth questions and notes together with lists of further reading to aid understanding of the issue. It also examines and discusses each substantive and procedural step in the trial process. Topics include jurisdiction of a court to consider a matter, limitations of actions, commencing proceedings, service, interlocutory proceedings, pleading, gathering evidence, trial and appeal, costs and practice directions. Each of the state, territory and federal procedures is covered.

Civil Procedure : Commentary and Materials (2nd ed)

This book provides a comprehensive analysis of the practical and theoretical issues encountered in Australian civil procedure, including alternative dispute resolution. Each chapter features in-depth questions and notes together with lists of further reading to aid understanding of the issue. It also examines and discusses each substantive and procedural step in the trial process. Topics include jurisdiction of a court to consider a matter, court adjudication under an adversarial system, alternative dispute resolution. limitations of actions, commencing proceedings, pleading, gathering evidence, trial and appeal, costs and enforcement. Each of the state, territory and federal procedures is covered.

Identifying discourses of moderation in higher education

Moderation of student assessment is a critical component of teaching and learning in contemporary universities. Yet, despite this, it tends to be marked by idiosyncratic and sporadic processes informed by liminal understanding. This paper, in the light of forthcoming radical national requirements for the declaration of moderation processes in tertiary curricula in Australia, will present four discourses of moderation we identified in a recent study in a Faculty of Education in a large metropolitan university. The discourses are equity, justification, community building and accountability. Together, they will act as a starting point for academics to review their beliefs and attitudes towards the moderation of student assessment.

Working with refugee survivors of torture and trauma : an opportunity for vicarious posttraumatic growth

Clinical work with people who have survived trauma carries a risk of vicarious traumatisation for the service provider, but also the potential for vicarious posttraumatic growth. Despite growing interest in this area, the effects of working with survivors of refugee-related trauma have remained relatively unexplored. The aim of the current study was to examine the lived experiences of people working on a daily basis with survivors of torture and trauma who had sought refuge in Australia. Seventeen clinical, administrative, and managerial staff from a not-for-profit organisation participated in a semi-structured interview that was later analysed using interpretive phenomenological analysis. Analysis of the data demonstrated that the entire sample reported symptoms of vicarious trauma (e.g., strong emotional reactions, intrusive images, shattering of existing beliefs) as well as vicarious posttraumatic growth (e.g., forming new relationships, increased self-understanding, greater appreciation of life). Moreover, effortful meaning making processes appeared to facilitate such positive changes. Reduction in the risks associated with this work, enhancement of clinician well-being, and improvement of therapeutic outcomes is a shared responsibility of the organisation and clinician. Without negating the distress of trauma work, clinicians are encouraged to more deeply consider the unique positive outcomes that supporting survivors can provide.

A comparison of Chinese and Australian early childhood mathematics

In the 21st century mathematics proficiency is synonymous with a numerate citizenry. In the past few decades young children’s ability to reason mathematically and develop mathematical proficiencies has been recognised. This paper explores the history of early childhood mathematics (ECME) that may explicate differences in Chinese and Australian contexts. Results of this review established that China and Australia are diametrically positioned in ECME. Influencing each countries philosophies and practices are their cultural beliefs. ECME in China and Australia must be culturally sustainable to achieve excellent outcomes for young children. Ongoing critique and review is necessary to ensure that ECME is meeting the needs of all teachers and children in their particular context. China and Australia with their rich contrasting philosophies can assist each other in their journeys to create exemplary ECME for the 21st century.

Peer assisted learning, skills development and Generation Y : a case study of a first year undergraduate law unit

The majority of current first year university students belong to Generation Y. Consequently, research suggests that, in order to more effectively engage them, their particular learning preferences should be acknowledged in the organisation of their learning environments and in the support provided. These preferences are reflected in the Torts Student Peer Mentor Program, which, as part of the undergraduate law degree at the Queensland University of Technology, utilises active learning, structured sessions and teamwork to supplement student understanding of the substantive law of Torts with the development of life-long skills. This article outlines the Program, and its relevance to the learning styles and experiences of Generation Y first year law students transitioning to university, in order to investigate student perceptions of its effectiveness – both generally and, more specifically, in terms of the Program’s capacity to assist students to develop academic and work-related skills.

Skill development and social inclusion via peer assisted learning in first-year higher education : an evaluation of student experiences across two law units

Because professions seek graduates who can 'collaborate, share skills and knowledge, and communicate' (Kruck and Reif, 2001, p 37), it is important that university graduates are not equipped solely with the content knowledge of their discipline, but also with prospective employment skills. Furthermore, when students 'interact more in positive ways with their teachers and peers, they gain more in terms of essential skills and competencies, such as critical thinking, problem~solving [and] effective communication' (NSSE, 2000, p 2)./n this way, peer assisted fellowing has the potential to enhance students' professional development, and provide the social inclusion and engagement necessary for effective learning. This session describes two peer assisted learning models embedded within first year QUT Faculty of Law units. Through a partnership between teaching staff, student mentors and mentees, the models aim to facilitate student socialisation whilst supplementing understanding of substantive law with the development of academic and work·related skills. Mentor and mentee perceptions, and program implications, are considered.

Does 2-wheeler experience affect behaviours and attitudes to 2-wheelers as a car driver?

• Car-bicycle and car-motorcycle crashes often serious • Car driver mostly at fault, often because of failure to see (Schramm et al, 2010) • Car drivers with motorcycling experience less likely to be involved in motorcycle crashes or be at fault (Brooks & Guppy, 1990; Magazzu et al., 2006) and hold more positive beliefs about motorcyclists (Crundall et al., 2008) • Does bicycle riding experience have the same benefits?

How to stop binge drinking and speeding motorists : effects of relational-interdependent self-construal and self-referencing on attitudes toward social marketing

How can marketers stop speeding motorists and binge drinking? Two experiments show that the beliefs consumers have about the degree to which they define themselves in terms of their close relationships (i.e., relational-interdependent self-construal (RISC)) offer useful insights into the effectiveness of communications for two key social marketing issues—road safety (Study 1, New Zealand sample) and alcohol consumption (Study 2, English sample). Further, self-referencing is a mechanism for these effects. Specifically, people who define themselves in terms of their close relationships (high-RISCs) respond most favorably to advertisements featuring a dyadic relationship (two people), and this favorable response is mediated by self-referencing. In contrast, people who do not include close relationships in their sense of self (low-RISCs) respond most favorably to self-reference advertisements featuring solitary models.

Civil procedure : commentary and materials (3rd ed.)

This book provides a comprehensive analysis of the practical and theoretical issues encountered in Australian civil procedure, including alternative dispute resolution. Each chapter features in-depth questions and notes together with lists of further reading to aid understanding of the issue. It also examines and discusses each substantive and procedural step in the trial process. Topics include jurisdiction of a court to consider a matter, alternative dispute resolution. limitations of actions, commencing proceedings, pleading, gathering evidence, trial and appeal, costs and practice directions. The procedures in the Supreme Courts of each of the states and Territories are covered, as well as those of the Federal Court of Australia.

Civil procedure : commentary and materials (4th ed)

This book provides a comprehensive analysis of the practical and theoretical issues encountered in Australian civil procedure, including alternative dispute resolution. Each chapter features in-depth questions and notes together with lists of further reading to aid understanding of the issue. It also examines and discusses each substantive and procedural step in the trial process. Topics include jurisdiction of a court to consider a matter, alternative dispute resolution, limitations of actions, commencing proceedings, pleading, gathering evidence, trial and appeal, costs and practice directions. Each of the state, territory and federal procedures is covered.

Coping resources, coping strategies and adaptation to organisational change : direct or buffering effects?

This study examined the effects of personal and social resources, coping strategies and appraised stress on employees' levels of anxiety and depression. In relation to the effects of resources and coping strategies, two different models were tested. The main effects model proposes that, irrespective of the level of stress, coping resources and coping strategies have direct effects on well-being. In contrast, the buffering model predicts that the buffering effects of coping resources and strategies are only evident at high levels of stress. One hundred lawyers completed a structured self-administered questionnaire that measured their personal and social resources, use of problem-focused and emotion-focused coping strategies, and appraisals of the stressfulness of the situation. Results revealed generally strong support for the main effects model in the prediction of employee levels of anxiety and depression. Lower levels of anxiety were linked to judgements of lower levels of organizational change, greater self-confidence, greater internality of control beliefs and less use of emotion-focused coping strategies. Lower levels of depression in employees were also linked to judgements of lower levels of organizational change, greater use of resources and less appraised stress. There was only limited support for the buffering effects model. Due to the small size of the sample, the findings need to be explored further in other contexts.