A class of self-stabilizing MCA learning algorithms

In this letter, we propose a class of self-stabilizing learning algorithms for minor component analysis (MCA), which includes a few well-known MCA learning algorithms. Self-stabilizing means that the sign of the weight vector length change is independent of the presented input vector. For these algorithms, rigorous global convergence proof is given and the convergence rate is also discussed. By combining the positive properties of these algorithms, a new learning algorithm is proposed which can improve the performance. Simulations are employed to confirm our theoretical results.

Playing in continuous spaces: Some analysis and extension of population-based incremental learning

As an alternative to traditional evolutionary algorithms (EAs), population-based incremental learning (PBIL) maintains a probabilistic model of the best individual(s). Originally, PBIL was applied in binary search spaces. Recently, some work has been done to extend it to continuous spaces. In this paper, we review two such extensions of PBIL. An improved version of the PBIL based on Gaussian model is proposed that combines two main features: a new updating rule that takes into account all the individuals and their fitness values and a self-adaptive learning rate parameter. Furthermore, a new continuous PBIL employing a histogram probabilistic model is proposed. Some experiments results are presented that highlight the features of the new algorithms.

Adaptation to being at-risk for Huntington's disease and the availability of genetic testing: Application of a stress and coping model

This study examined the utility of a stress/coping model in explaining adaptation in two groups of people at-risk for Huntington's Disease (HD): those who have not approached genetic testing services (non-testees) and those who have engaged a testing service (testees). The aims were (1) to compare testees and non-testees on stress/coping variables, (2) to examine relations between adjustment and the stress/coping predictors in the two groups, and (3) to examine relations between the stress/coping variables and testees' satisfaction with their first counselling session. Participants were 44 testees and 40 non-testees who completed questionnaires which measured the stress/coping variables: adjustment (global distress, depression, health anxiety, social and dyadic adjustment), genetic testing concerns, testing context (HD contact, experience, knowledge), appraisal (control, threat, self-efficacy), coping strategies (avoidance, self-blame, wishful thinking, seeking support, problem solving), social support and locus of control. Testees also completed a genetic counselling session satisfaction scale. As expected, non-testees reported lower self-efficacy and control appraisals, higher threat and passive avoidant coping than testees. Overall, results supported the hypothesis that within each group poorer adjustment would be related to higher genetic testing concerns, contact with HD, threat appraisals, passive avoidant coping and external locus of control, and lower levels of positive experiences with HD, social support, internal locus of control, self-efficacy, control appraisals, problem solving, emotional approach and seeking social support coping. Session satisfaction scores were positively correlated with dyadic adjustment, problem solving and positive experience with HD, and inversely related to testing concerns, and threat and control appraisals. Findings support the utility of the stress/coping model in explaining adaptation in people who have decided not to seek genetic testing for HD and those who have decided to engage a genetic testing service.

Measuring impacts of an holistic farm business management training program

A case study approach within an action research framework incorporating qualitative and quantitative domains was adopted to explore the impact on Queensland farmers of a farm business management extension programme. Three new indices were developed to quantify changes perceived by participants. The first measure, the Bennett Change Index, provided statistically significant evidence that attitudinal and behavioural changes were more frequent in participants with less formal education, but also more frequent in participants who had high urbanisation and self-directed learning index scores. The other 2 new indices, Management Constructs Change and Management Objectives Change, provided evidence of statistically significant changes in participant beliefs about, and attitudes towards, farm business management. Although highly correlated with each other, these changes were unrelated statistically to any of 6 other commonly used biographical or psychometric indices employed; including level of formal education. It is concluded that these new measures, with context-relevant modifications, have potential as aids to programme impact evaluation in a range of agricultural and wider applications. They may provide insights into personal psychological issues that complement direct behavioural measures of change.

Predictors of cultural adjustment: Intergroup status relations and boundary permeability

We examined intergroup predictors of cultural adjustment among Asian international students in Australia. Sociostructural beliefs (status, legitimacy, and permeability) and initial adjustment were assessed (N = 113) at Time 1, and measures of adjustment were obtained (N = 80) at Time 2 eight weeks later. International students who perceived their cultural group to be relatively low in status experienced lower levels of psychological adjustment. Also, as expected, the effects of status were moderated by perceptions of both the permeability of intergroup boundaries and the legitimacy of the status differential. At high levels of legitimacy, perceptions of permeable group boundaries were associated with better psychological, sociocultural, and academic adjustment among international students perceiving their group to be low in status, but lower levels of adjustment among students who perceived their group to be high in status. At low levels of legitimacy, irrespective of group status position, perceived permeability was not related to adjustment.

Biologically inspired joint control for a humanoid robot

The GuRm is a 1.2m tall, 23 degree of freedom humanoid consuucted at the University of Queensland for research into humanoid robotics. The key challenge being addressed by the GuRw projcct is the development of appropriate learning strategies for control and coodinadon of the robot’s many joints. The development of learning strategies is Seen as a way to sidestep the inherent intricacy of modeling a multi-DOP biped robot. This paper outlines the approach taken to generate an appmpria*e control scheme for the joinis of the GuRoo. The paper demonsrrates the determination of local feedback control parameters using a genetic algorithm. The feedback loop is then augmented by a predictive modulator that learns a form of feed-fonward control to overcome the irregular loads experienced at each joint during the gait cycle. The predictive modulator is based on thc CMAC architecture. Results from tats on the GuRoo platform show that both systems provide improvements in stability and tracking of joint control.

A longitudinal study of learning for a group of indigenous Australian university students: Dissonant conceptions and strategies

Conceptions of learning and strategies used by 15 indigenous students in three Australian universities were studied longitudinally over three years. Their academic achievements were good, but at a high cost in terms of time and effort. In spite of the fact that almost half of the students expressed higher-order (qualitative) conceptions of learning in the first year and more in the second and third years, all of the students reported using highly repetitive strategies to learn. That is, they did not vary their way of learning, reading or writing in the beginning of their studies and less than half of them did so at the end of the three years. It is argued that encountering variation in ways of learning is a prerequisite for the development of powerful ways of learning and studying.