Are combination forecasts of S&P 500 volatility statistically superior?

Forecasting volatility has received a great deal of research attention, with the relative performances of econometric model based and option implied volatility forecasts often being considered. While many studies find that implied volatility is the pre-ferred approach, a number of issues remain unresolved, including the relative merit of combining forecasts and whether the relative performances of various forecasts are statistically different. By utilising recent econometric advances, this paper considers whether combination forecasts of S&P 500 volatility are statistically superior to a wide range of model based forecasts and implied volatility. It is found that a combination of model based forecasts is the dominant approach, indicating that the implied volatility cannot simply be viewed as a combination of various model based forecasts. Therefore, while often viewed as a superior volatility forecast, the implied volatility is in fact an inferior forecast of S&P 500 volatility relative to model-based forecasts.

An empirical investigation of the level effect in Australian interest rates

An extensive literature examines the dynamics of interest rates, with particular attention given to the positive relationship between interest-rate volatility and the level of interest rates—the so-called level effect. This paper examines the interaction between the estimated level effect and competing parameterisations of interest-rate volatility for the Australian yield curve. We adopt a new methodology that estimates elasticity in a multivariate setting that explicitly accommodates the correlations that exist between various yield factors. Results show that significant correlations exist between the residuals of yield factors and that such correlations do indeed impact on model estimates. Within the multivariate setting, the level of the short rate is shown to be a crucial determinant of the conditional volatility of all three yield factors. Measures of model fit suggest that, in addition to the usual level effect, the incorporation of GARCH effects and possible regime shifts is important

Learning wellness : how ageing Australians experience health information literacy

Given identified synergies between information use and health status greater understanding is needed about how people use information to learn about their health. This article presents the findings of preliminary research into health information literacy which sought to explore how this is phenomenon is experienced among ageing Australians. Analysis of data from semi-structured interviews has revealed six different ways ageing Australians experience using information to learn about their health within one aspect of community life. Health information literacy is a new terrain for information literacy research endeavours and one which warrants further attention by the profession to foster and promote within the community.

Can tissue engineering concepts advance tumor biology research?

Advances in tissue engineering have traditionally led to the design of scaffold- or matrix-based culture systems that better reflect the biological, physical and biochemical environment of the natural extracellular matrix. Although their clinical applications in regenerative medicine tend to receive most of the attention, it is obvious that other areas of biomedical research could be well served by the powerful tools that have already been developed in tissue engineering. In this article, we review the recent literature to demonstrate how tissue engineering platforms can enhance in vitro and in vivo models of tumorigenesis and thus hold great promise to contribute to future cancer research.

Pedagogical practice after the information age

These chapters bare witness to various manifestations of an emerging global mind set that is marked not by coherence and a single story but by multiple and layered possibility. The authors all see, from often quite different positions, that the future health of society lies in diversity and a social activism that is grounded in the local actions of individuals. Education will play a central role in empowering this activism and it is to this multiple future that this book turns its attention.

Signs, symptoms and comorbidities in contact lens-related microbial keratitis

Purpose: The aim of this study was to characterize the clinical signs, symptoms, and ocular and systemic comorbidities in a large case series of contact lens-related microbial keratitis. Methods: Two hundred ninety-seven cases of contact lens-related microbial keratitis, aged between 15 and 64 years were detected through surveillance of hospital and community based ophthalmic practitioners in Australia and New Zealand. Full clinical data were available for 190 cases and 90 were interviewed by telephone. Clinical data included the size, location, and degree of anterior chamber response. Symptom data were available from the practitioner and from participant self-report. Associations between symptoms and disease severity were evaluated. Data on ocular and systemic disease were collected from participants and practitioners. The frequency of comorbidities was compared between the different severities of disease and to population norms. Results: More severe disease was associated with greater symptom severity and pain was the most prevalent symptom reported. Ninety-one percent of cases showed progression of ocular symptoms after lens removal, and symptom progression was associated with all severities of disease. Twenty-five percent of cases reported prior episodes requiring emergency attention. Thyroid disease (p 0.05) and self-reported poor health (p 0.001) were more common in cases compared with age-matched population norms. Discussion: Information on the signs, symptoms, and comorbidities associated with contact lens-related microbial keratitis may be useful in patient education and for practitioners involved in the fitting of lenses and management of complications. Although pain was the most common symptom experienced, progression of symptoms despite lens removal was close to universal. Poor general health, particularly respiratory disease and thyroid disease was more common in cases than in the general population, which may prompt practitioners to recommend flexibility in wear schedules when in poor health or the selection of a lower risk wear schedule in at risk patients

The well-being of older job-seekers : implications for the labour force participation agenda

Throughout the developed world demographic trends and their forecast consequences are attracting the attention of governments, academics, think tanks and the popular press alike. Population aging, in particular, is the focus of many and has generated extensive debate. Approaches commonly advocated in the literature include a mix of ‘population', ‘participation’ and ‘productivity’ measures. Immigration and population policy alongside industry reform and related productivity initiatives are also being pursued. Participation, however, remains a key element of the demographic change policy response. Evidence suggests however, that these approaches are unlikely to deliver the necessary labour force volumes. This has prompted a shift in the participation agenda to also include a stronger focus on skilled and experienced older workers. The literature suggests, however, that the current suite of practices are less than effective for the long-term unemployed, previously long-tenured older workers with specialised skills and trade-displaced workers. Adverse health and human capital outcomes often associated with social disadvantage are complicating factors. This reminds of the complexity of the challenge in seeking to deliver social equity to the disadvantaged and suggests a need for an alternative policy architecture. By integrating the three concepts of health capital, human capital and social capital we show how policy has to change if the older age cohorts of jobseekers are to be assisted to remain employable. This review includes an examination of current policy, a consolidation of the literature and original data.

'Black is beautiful', and Indigenous : Aboriginal authorship in Australian popular music

The ‘black is beautiful’ movement began in the United States in the early sixties, and changed mainstream attitudes towards the body, fashion and personal aesthetics, gaining African American people a new sense of pride in being – and being called – ‘black’. In Australia the movement also had implications for changing the political meanings of ‘black’ in white society. However, it is not until the last decade, through the global influence of Afro-American music, that a distinctly Indigenous sense of black sexiness has captured the attention of mainstream audiences. The article examines such recent developments, and suggests that, through the appropriation of Afro-American aesthetics and styles, Indigenous producers and performers have developed new forms of Indigenous public agency, demonstrating that black is beautiful, and Indigenous.

Closing the cultural distance gap: managing value-based knowledge in MNC by using MEP

Today more than ever, generating and managing knowledge is an essential source of competitive advantage for every organization, and particularly for Multinational corporations (MNC). However, despite the undisputed agreement about the importance of creating and managing knowledge, there are still a large number of corporations that act unethically or illegally. Clearly, there is a lack of attention in gaining more knowledge about the management of ethical knowledge in organizations. This paper refers to value-based knowledge, as the process of recognise and manage those values that stand at the heart of decision-making and action in organizations. In order to support MNCs in implementing value-based knowledge process, the managerial ethical profile (MEP) has been presented as a valuable tool to facilitate knowledge management process at both the intra-organizational network level and at the inter-organizational network level.

Mathematical modelling of muscle recruitment and function in the lumbar spine

Low back pain is an increasing problem in industrialised countries and although it is a major socio-economic problem in terms of medical costs and lost productivity, relatively little is known about the processes underlying the development of the condition. This is in part due to the complex interactions between bone, muscle, nerves and other soft tissues of the spine, and the fact that direct observation and/or measurement of the human spine is not possible using non-invasive techniques. Biomechanical models have been used extensively to estimate the forces and moments experienced by the spine. These models provide a means of estimating the internal parameters which can not be measured directly. However, application of most of the models currently available is restricted to tasks resembling those for which the model was designed due to the simplified representation of the anatomy. The aim of this research was to develop a biomechanical model to investigate the changes in forces and moments which are induced by muscle injury. In order to accurately simulate muscle injuries a detailed quasi-static three dimensional model representing the anatomy of the lumbar spine was developed. This model includes the nine major force generating muscles of the region (erector spinae, comprising the longissimus thoracis and iliocostalis lumborum; multifidus; quadratus lumborum; latissimus dorsi; transverse abdominis; internal oblique and external oblique), as well as the thoracolumbar fascia through which the transverse abdominis and parts of the internal oblique and latissimus dorsi muscles attach to the spine. The muscles included in the model have been represented using 170 muscle fascicles each having their own force generating characteristics and lines of action. Particular attention has been paid to ensuring the muscle lines of action are anatomically realistic, particularly for muscles which have broad attachments (e.g. internal and external obliques), muscles which attach to the spine via the thoracolumbar fascia (e.g. transverse abdominis), and muscles whose paths are altered by bony constraints such as the rib cage (e.g. iliocostalis lumborum pars thoracis and parts of the longissimus thoracis pars thoracis). In this endeavour, a separate sub-model which accounts for the shape of the torso by modelling it as a series of ellipses has been developed to model the lines of action of the oblique muscles. Likewise, a separate sub-model of the thoracolumbar fascia has also been developed which accounts for the middle and posterior layers of the fascia, and ensures that the line of action of the posterior layer is related to the size and shape of the erector spinae muscle. Published muscle activation data are used to enable the model to predict the maximum forces and moments that may be generated by the muscles. These predictions are validated against published experimental studies reporting maximum isometric moments for a variety of exertions. The model performs well for fiexion, extension and lateral bend exertions, but underpredicts the axial twist moments that may be developed. This discrepancy is most likely the result of differences between the experimental methodology and the modelled task. The application of the model is illustrated using examples of muscle injuries created by surgical procedures. The three examples used represent a posterior surgical approach to the spine, an anterior approach to the spine and uni-lateral total hip replacement surgery. Although the three examples simulate different muscle injuries, all demonstrate the production of significant asymmetrical moments and/or reduced joint compression following surgical intervention. This result has implications for patient rehabilitation and the potential for further injury to the spine. The development and application of the model has highlighted a number of areas where current knowledge is deficient. These include muscle activation levels for tasks in postures other than upright standing, changes in spinal kinematics following surgical procedures such as spinal fusion or fixation, and a general lack of understanding of how the body adjusts to muscle injuries with respect to muscle activation patterns and levels, rate of recovery from temporary injuries and compensatory actions by other muscles. Thus the comprehensive and innovative anatomical model which has been developed not only provides a tool to predict the forces and moments experienced by the intervertebral joints of the spine, but also highlights areas where further clinical research is required.

"Men at play : masculinities in Australian theater since the 1950s" -- By Jonathan Bollen, Adrian Kiernander and Bruce Parr

Adopting a thematic rather than chronological arrangement, this co-authored book surveys representations of men and masculinity in post-war Australian theater. Its searching and sophisticated analyses draw upon playscripts, critical records and archival material, including screen versions of stage productions. The study is organized around two distinct periods of Australian theater history: the 1950s to 1970, during which time a national theatremovement flourished, and the mid-1980s onward.Whilst some attention is given to different genres, discussion centers primarily on realist works from the mainstream. Several plays usually omitted from orthodox theater histories, such as Barry Pree’s A Fox in the Night (1959), are given detailed treatments.

Co-creative labour

This article introduces a special issue on the topic of co-creative labour. The term co-creation is used to describe the phenomenon of consumers increasingly participating in the process of making and circulating media content and experiences. Practices of user-created content and user-led innovation are now significant sources of both economic and cultural value. But how should we understand and analyse these value-generating activities? What are the identities and forms of agency that constitute these emerging co-creative relations? Should we define these activities as a form of labour and what are the implications and impacts of co-creative practices on the employment conditions and professional identities of people working in the creative industries? In answering these questions we argue that careful attention must be paid to how the participants themselves (both professional and non-professional, commercial and non-commercial) negotiate and navigate the meanings and possibilities of these emerging co-creative relationships for mutual benefit. Co-Creative media production is perhaps a disruptive agent of change that sits uncomfortably with our current understandings and theories of work and labour. The articles in this special issue follow and unpack the often diverse and contradictory ways in which the participants themselves use and remake the social categories of work and labour as they seek to co-ordinate and contest co-creative media practices.

Image synthesis based on a model of human vision

Modern computer graphics systems are able to construct renderings of such high quality that viewers are deceived into regarding the images as coming from a photographic source. Large amounts of computing resources are expended in this rendering process, using complex mathematical models of lighting and shading. However, psychophysical experiments have revealed that viewers only regard certain informative regions within a presented image. Furthermore, it has been shown that these visually important regions contain low-level visual feature differences that attract the attention of the viewer. This thesis will present a new approach to image synthesis that exploits these experimental findings by modulating the spatial quality of image regions by their visual importance. Efficiency gains are therefore reaped, without sacrificing much of the perceived quality of the image. Two tasks must be undertaken to achieve this goal. Firstly, the design of an appropriate region-based model of visual importance, and secondly, the modification of progressive rendering techniques to effect an importance-based rendering approach. A rule-based fuzzy logic model is presented that computes, using spatial feature differences, the relative visual importance of regions in an image. This model improves upon previous work by incorporating threshold effects induced by global feature difference distributions and by using texture concentration measures. A modified approach to progressive ray-tracing is also presented. This new approach uses the visual importance model to guide the progressive refinement of an image. In addition, this concept of visual importance has been incorporated into supersampling, texture mapping and computer animation techniques. Experimental results are presented, illustrating the efficiency gains reaped from using this method of progressive rendering. This visual importance-based rendering approach is expected to have applications in the entertainment industry, where image fidelity may be sacrificed for efficiency purposes, as long as the overall visual impression of the scene is maintained. Different aspects of the approach should find many other applications in image compression, image retrieval, progressive data transmission and active robotic vision.

Bicycle helmet wearing among adolescents

Adolescents experience many benefits from bicycling; however, there are also potentially significant injury consequences. One effective counter-measure for the prevention of adolescent bicycling injuries is to promote bicycle helmet wearing. An overview is provided of injury risks of bicycle riding with particular attention to the role of helmet wearing and associated countermeasures such as legislation and school and community approaches. The findings are presented of a study conducted in Australia that examined the effectiveness of a theory-based injury prevention program, Skills for Preventing Injury in Youth (SPIY) for ninth-grade students (age 13 to 14 years). The findings showed a significant, 20.2% decrease in cycling without a helmet among the intervention students (n = 360) and no change for the students in the comparison group (n = 363) after 6 months. In addition, it was found that failing to wear a helmet was significantly associated with engaging in other transport-related risks, being male, having friends who do not wear a helmet and are specific targets of change in the SPIY program, showing a negative attitude toward risk, failing to intervene in friends' risk-taking, and having low knowledge of first aid. Overall, the SPIY program appeared to be an effective theory-based intervention to increase helmet wearing among early adolescents, a group not often targeted in school and community helmet-wearing programs.

Innovation

Innovation can be defined broadly to include the development and uptake of new technology, the introduction of new products, the utilisation of new market opportunities and the implementation of new business processes including new forms of work organisation or management structures and approaches. Innovation, or the commercial application of new knowledge, is of increasing importance to economic competitiveness given the growth in production and trade in high technology industries and knowledge intensive service sectors such as business services (Edquist, Hommen and McKelvey 2001). An important field of innovation in modern economies is associated with the rapid development and application of information and communications technologies (ICTs). ICTs constitute an increasing share of value added, growth and employment and also impact on employment and productivity in other industry sectors. The structural transformation of modern economies associated with ICTs has led to an increase in the importance of information and knowledge resources (rather than physical capital) as inputs or factors of production. Technology and product innovations are often given central attention in innovation research, however, organisational and managerial changes have been recognised as critical. Over the last two decades, understandings of the nature and process of innovation have advanced significantly. In the 1950s and 1960s, there was a view that innovation resulted from basic research, or in essence that scientific research acted as a 'push' for innovation. As such there was a great deal of emphasis on formal research and development, undertaken either by governments or research and development units within business organisations. Radical innovations involving new products and new technological trajectories were thought to derive from basic research (Freeman 1995).