Testing the weak-form version of the efficient markets hypothesis

This thesis examines the weak-form efficiency of the Australian stock market using data from Australia's major banking stocks, the Banking Index and the All Ordinaries Index. Applying a combination of existing technical analysis indicators, coupled with a relatively new technique known as Sequential (TM) reveals that the Australian stock market is weak-form inefficient.

The end of economic growth? A contracting threshold hypothesis

This paper argues that GDP growth in both developed and developing countries has associated costs that can outweigh the benefits and thus reduce sustainable well-being. This conclusion is based upon the findings of empirical applications of the Genuine Progress Indicator (GPI) to a range of countries in the Asia-Pacific region. The studies conducted on seven Asia-Pacific countries indicate that, in the case of five of the seven nations, more recent GDP growth has reduced the sustainable well-being experienced by the average citizen residing within them. Moreover, the threshold point at which the costs of GDP growth outweigh the benefits appears to be contracting (i.e., occurring at a much lower per capita level of GDP). This paper therefore introduces a new contracting threshold hypothesis: as the economies of the Asia-Pacific region and the world collectively expand in a globalised economic environment, there is a contraction over time in the threshold level of per capita GDP. As a consequence, the threshold point confronting growth late-comers (i.e., developing countries) occurs at a much lower level of sustainable welfare than what wealthy nations currently enjoy. The consequences of this for developing countries are clearly significant and require a new approach to economic development.

The median and its extensions

We review various representations of the median and related aggregation functions. An advantage of the median is that it discards extreme values of the inputs, and hence exhibits a better central tendency than the arithmetic mean. However, the value of the median depends on only one or two central inputs. Our aim is to design median-like aggregation functions whose value depends on several central inputs. Such functions will preserve the stability of the median against extreme values, but will take more inputs into account. A method based on graduation curves is presented.

Dopamine dysregulation syndrome : implications for a dopamine hypothesis of bipolar disorder

Objective: Rational therapeutic development in bipolar is hampered by a lack of pathophysiological model. However, there is a wealth of converging data on the role of dopamine in bipolar disorder. This paper therefore examines the possibility of a dopamine hypothesis for bipolar disorder.

Method: A literature search was conducted using standard search engines Embase, PyschLIT, PubMed and MEDLINE. In addition, papers and book chapters known to the authors were retrieved and examined for further relevant articles.

Results: Collectively, in excess of 100 articles were reviewed from which approximately 75% were relevant to the focus of this paper.

Conclusion: Pharmacological models suggest a role of increased dopaminergic drive in mania and the converse in depression. In Parkinson’s disease, administration of high-dose dopamine precursors can produce a ‘maniform’ picture, which switches into a depressive analogue on withdrawal. It is possible that in bipolar disorder there is a cyclical process, where increased dopaminergic transmission in mania leads to a secondary down regulation of dopaminergic receptor sensitivity over time. This may lead to a period of decreased dopaminergic transmission, corresponding with the depressive phase, and the repetition of the cycle. This model, if verified, may have implications for rational drug development.

The developmental stress hypothesis: A special case of the evolution of condition-dependent sexual traits

The idea that sexually selected traits might be condition dependent is far from novel (Zahavi 1975); however, the developmental stress hypothesis was proposed as a special case because of a highly plausible mechanism: the development of the neural circuits controlling song output coincides with a period of time during which developing birds are likely to be susceptible to stress. The elegant aspect of the hypothesis is that the mechanism is defined and effects can be readily tested (Nowicki et al. 1998; Buchanan et al. 2003). Compared with more general hypotheses about the evolution of condition-dependent sexual traits (Buchanan 2000), the second particularly interesting aspect of the developmental stress hypothesis is that, in some species, individuals may suffer historical markers of stress. This is because in species with a fixed period for neural growth and song learning, there is no possibility for compensation in later life for stress experienced during early development. Females using such a marker of stress may benefit by obtaining a partner whose other cognitive functions have not been impaired by stress.

Testing the expectations hypothesis for interest rate term structure : some Australian evidence

Many test results are found inconsistent with the expectations hypothesis of the term structure. The aim of this paper is to re-examine the expectations hypothesis of the term structure using the Australian interest rate data from 1969(7) to 1995(7). We start with the cointegration test on R_t, r_t, and S_t followed by the Granger causality test from S_t to ∇ r_t. Finally we carry out the VAR model of cross-equation restrictions test. Our findings show that there is no conclusive rejection of the expectations hypothesis of the term structure.

Hypothesis verification using parametric models and active vision strategies

This paper proposes a methodology for determining the shape and ultimately the functionality of objects from intensity images; 2D analytic functions are used to track 3D features during known camera motions. Three analytic functions are proposed that describe the relationship between pairs of points that are either stationary or moving depending on whether the points are on occluding boundaries or otherwise. Many of the problems of correspondence are reduced by using foveation, known camera motion, and active vision methods. The three analytic functions are shown to enable hypothesis refinement of the functionality of a number of 3D objects without full 3D information about the shape.

Emerging hypothesis verification using function-based geometric models and active vision strategies

This paper describes an investigation into the use of parametric 2D models describing the movement of edges for the determination of possible 3D shape and hence function of an object. An assumption of this research is that the camera can foveate and track particular features. It is argued that simple 2D analytic descriptions of the movement of edges can infer 3D shape while the camera is moved. This uses an advantage of foveation i.e. the problem becomes object centred. The problem of correspondence for numerous edge points is overcome by the use of a tree based representation for the competing hypotheses. Numerous hypothesis are maintained simultaneously and it does not rely on a single kinematic model which assumes constant velocity or acceleration. The numerous advantages of this strategy are described.

A nonlinear approach to testing the unit root null hypothesis : an application to international health expenditures

In this article, we examine the unit root null hypothesis for per capita total Health Expenditures (HEs), per capita private HEs and per capita public HEs for 29 Organization for Economic Co-operation and Development (OECD) countries. The novelty of our work is that we use a new nonlinear unit root test that allows for one structural break in the data series. We find that for around 45% of the countries, we are able to reject the unit root hypothesis for each of the three HE series. Moreover, using Monte Carlo simulations, we show that our proposed unit root model has better size and power properties than the widely used Augmented Dickey–Fuller (ADF) and Lagrange Multiplier (LM) type tests.

Aggregation for Atanassov's intuitionistic and interval valued fuzzy sets: the median operator

Atanassov's intuitionistic fuzzy sets (AIFS) and interval valued fuzzy sets (IVFS) are two generalizations of a fuzzy set, which are equivalent mathematically although different semantically. We analyze the median aggregation operator for AIFS and IVFS. Different mathematical theories have lead to different definitions of the median operator. We look at the median from various perspectives: as an instance of the intuitionistic ordered weighted averaging operator, as a Fermat point in a plane, as a minimizer of input disagreement, and as an operation on distributive lattices. We underline several connections between these approaches and summarize essential properties of the median in different representations.

Annual feedback is an effective tool for a sustained increase in calcium intake among older women

We aimed to optimize calcium intake among the 2,000+ older women taking part in the Vital D study. Calcium supplementation was not included in the study protocol. Our hypothesis was that annual feedback of calcium intake and informing women of strategies to improve calcium intake can lead to a sustained increase in the proportion of women who consume adequate levels of the mineral. Calcium intake was assessed on an annual basis using a validated short food frequency questionnaire (FFQ). Supplemental calcium intake was added to the dietary estimate. Participants and their nominated doctor were sent a letter that the participant’s estimated daily calcium intake was adequate or inadequate based on a cutoff threshold of 800 mg/day. General brief statements outlining the importance of an adequate calcium intake and bone health were included in all letters. At baseline, the median daily consumption of calcium was 980 mg/day and 67 percent of 1,951 participants had calcium intake of at least 800 mg per day. Of the 644 older women advised of an inadequate calcium intake at baseline (< 800 mg/day), 386 (60%) had increased their intake by at least 100 mg/day when re-assessed twelve months later. This desirable change was sustained at 24 months after baseline with almost half of these women (303/644) consuming over 800 mg calcium per day. This study devised an efficient method to provide feedback on calcium intake to over 2,000 older women. The improvements were modest but significant and most apparent in those with a low intake at baseline. The decreased proportion of these women with an inadequate intake of calcium 12- and 24-months later, suggests this might be a practical, low cost strategy to maintain an adequate calcium intake among older women.

Upgrading arc median shortest path problem for an urban transportation network

In this paper, we propose an algorithm for an upgrading arc median shortest path problem for a transportation network. The problem is to identify a set of nondominated paths that minimizes both upgrading cost and overall travel time of the entire network. These two objectives are realistic for transportation network problems, but of a conflicting and noncompensatory nature. In addition, unlike upgrading cost which is the sum of the arc costs on the path, overall travel time of the entire network cannot be expressed as a sum of arc travel times on the path. The proposed solution approach to the problem is based on heuristic labeling and exhaustive search techniques, in criteria space and solution space, respectively. The first approach labels each node in terms of upgrading cost, and deletes cyclic and infeasible paths in criteria space. The latter calculates the overall travel time of the entire network for each feasible path, deletes dominated paths on the basis of the objective vector and identifies a set of Pareto optimal paths in the solution space. The computational study, using two small-scale transportation networks, has demonstrated that the algorithm proposed herein is able to efficiently identify a set of nondominated median shortest paths, based on two conflicting and noncompensatory objectives.