Home range, habitat use and movements by the little raven (Corvus mellori) in a coastal peri-urban landscape

Context In peri-urban environments, high availability of anthropogenic resources may result in relatively high abundances of some species, with potentially negative implications for other native biota. Effective management of such impacts requires understanding of the spatial ecology of problem species. However, home range and habitat use have not been described for the little raven (Corvus mellori), a superabundant native predator that occurs in urban and natural habitats, including those where threatened shorebirds breed. Aims The aim of this study was to provide basic information on little raven home range, habitat use and movements in a coastal peri-urban landscape. Methods Between October 2011 and January 2012 we radio-tracked 20 little ravens captured in a coastal wetland (near Melbourne, Australia). Key results Little ravens were highly mobile, moving up to 9.9km in an hour (median≤2km), and had large ranges: Minimum Convex Polygons were 1664-9989ha (median≤3362ha). Although most birds used both anthropogenic and natural habitats, some birds strongly selected for coastal wetland habitat. Birds used multiple roosts during the study period, most of which occurred in grassland (58.7%) or urban (22.3%) areas. Movement of up to 8.3km (median≤2.2km) between roosts during the night was also detected. Conclusions Ravens were highly mobile and used large home ranges and a variety of habitats, with habitat preferences varying between birds. Implications Considering the large home ranges and inter-individual variation in habitat preferences of little raven populations, localised management to reduce their impacts on breeding shorebirds is unlikely to be successful. Journal compilation

Multicenter randomized controlled trial of a home walking intervention after outpatient cardiac rehabilitation on health-related quality of life in women

BACKGROUND: Poor health-related quality of life (HRQL) has been shown to be predictive of adverse outcomes in cardiac patients. As women with coronary heart disease have been shown to have lower HRQL than men with coronary heart disease, women are at greater risk of a poor clinical outcome. This study tested the effect of a 12-week home walking intervention after completion of outpatient cardiac rehabilitation (OCR) on HRQL and maintenance of physical activity among women. DESIGN: Multicenter two-group randomized trial. METHODS: After completion of OCR, participants were randomly allocated to the intervention or usual care groups. The outcomes were HRQL (assessed using the MacNew Heart Disease HRQL instrument) and self-reported physical activity (assessed using the Stages of Change model of exercise behavior) at 3, 6, and 12 months after OCR. RESULTS: Seventy-two women were randomized to the intervention and 81 to usual care. Attrition was greater in the treatment group (13 vs. 1%). HRQL scores increased relative to the base level in both arms and were significantly higher in the intervention group at 6 months, but not at 3 or 12 months. Maintenance of physical activity declined over time in both groups, however, this decline was significantly reduced among women in the intervention group. CONCLUSION: HRQL improved in both groups, but seemed to increase earlier among women in the intervention group. As maintenance of physical activity was higher among women in the intervention group, this minimal intervention could be used to facilitate women's progression from supervised to independent exercise.

Modelling personal preferences for Top-N movie recommendations

Modelling the temporal dynamics of personal preferences is still under-developed despite the rapid development of personalization. In this paper, we observe that the user preference styles tend to change regularly following certain patterns in the context of movie recommendation systems. Therefore, we propose a Preference Pattern model to capture the user preference styles and their temporal dynamics, and apply this model to improve the accuracy of the Top-N movie recommendations. Precisely, a preference pattern is defined as a set of user preference styles sorted in a time order. The basic idea is to model user preference styles and their temporal dynamics by constructing a representative subspace with an Expectation-Maximization (EM)-like algorithm, which works in an iterative fashion by refining the global and the personal preference styles simultaneously. Then, the degree which the recommendations match the active user's preference styles, can be estimated by measuring its reconstruction error from its projection on the representative subspace. The experiment results indicate that the proposed model is robust to the data sparsity problem, and can significantly outperform the state-of-the-art algorithms on the Top-N movie recommendations in terms of accuracy.

Point of View: Going Home: Far and Near

Nikky-Guninder K. Singh on going home to Punjab.

Fatores-chave na qualidade de sistemas de home broker : uma análise teórico-empírica

This work has as main objective the development of a key factors¿ model for the quality of Home Broker systems. An explanatory research was performed, based on a quantitative approach. To achieve this goal, some theoretical models of technology acceptance (TAM, TRA, TPB and IDT), reliability and quality of service were reviewed. It was proposed an extended key factors¿ model and developed a questionnaire, which was the research instrument used in this study. The questionnaire was applied over the Internet, from which was obtained a participation of 113 valid respondents, all of them users of Home Broker system. Once performed the data collection, statistical tests were used for the Factorial Analysis in order to achieve a definitive model. The key factors found were Perceived Usefulness, Perceived Ease of Use, Subjective Norms, Compatibility, Reliability and Relative Advantage. Some hypotheses from the model were also tested to investigate the relationship between the importance given to the factors and the resulting degree of satisfaction about quality of service. As a result of the study, a key factors¿ model for the quality of Home Broker systems was established, and identified that the factor Compatibility" has more explanatory power than the others."

R&D investment, international trade, and home market and competitiveness efects

We analyze the effects of R&D investment on international trade. The importance of studying this comes from the fact that one of the most important characteristics of modern industrial organization is that firms try to influence market behavior through strategic variables as R&D. Moreover international competition between firms is, more and more, also centered in R&D competition (besides output and price competition). With this in mind, we develop an oligopolist reciprocal-markets model where firms engage in R&D investment to achieve future reductions in marginal costs. We find ‘home market effects’ at the level of R&D investment, i.e.: firms located in countries that host a higher share of skilled-labor perform higher levels of R&D investment. As consequence, firms in these countries are more competitive than firms in other countries, and as such they can penetrate more easily foreign markets. As result of this ‘competitiveness effect’, countries where these firms are located run trade surplus, while countries where firms perform lower levels of R&D investment incur in trade deficits.

Home bias no mercado de capitais brasileiro : um estudo sobre a custódia de investidores em ações

A presente dissertação apresenta uma análise da concentração do portfólio de a-ções de investidores brasileiros nas próprias empresas onde trabalham com o intuito de observar se o Home Bias se aplica à amostra analisada. Nosso estudo foi reali-zado com uma amostra extraída da custódia de 86 clientes de uma corretora de va-lores mobiliários, sendo estes dados reais de mercado. Restringimos a seleção da amostra de forma que metade fosse de clientes que trabalham em empresas de ca-pital aberto e a outra metade não. Foi feita análise cross section de quanto os inves-tidores alocam em ações das empresas para a qual trabalham e verificou-se qual o percentual desta participação em seus portfólios, em comparação a uma amostra de controle de investidores que não trabalham nesta mesma empresa. Além destas a-nálises, separamos a amostra pelo valor total do portfólio e realizamos os mesmos estudos com estes dois grupos diferentes da amostra. Como uma análise de robus-tez, identificamos empresas listadas que não adotam a remuneração com ações como uma sub-amostra do estudo. Como resultado, encontramos evidências de que os funcionários investem significativamente mais (seja em proporção do portfólio ou em valores) em ações das empresas onde trabalham em relação aos demais inves-tidores, evidenciando um viés de familiaridade na tomada de decisão de investimen-tos.