User evaluation of a market-based recommender system

Recommender systems have been developed for a wide variety of applications (ranging from books, to holidays, to web pages). These systems have used a number of different approaches, since no one technique is best for all users in all situations. Given this, we believe that to be effective, systems should incorporate a wide variety of such techniques and then some form of overarching framework should be put in place to coordinate them so that only the best recommendations (from whatever source) are presented to the user. To this end, in our previous work, we detailed a market-based approach in which various recommender agents competed with one another to present their recommendations to the user. We showed through theoretical analysis and empirical evaluation with simulated users that an appropriately designed marketplace should be able to provide effective coordination. Building on this, we now report on the development of this multi-agent system and its evaluation with real users. Specifically, we show that our system is capable of consistently giving high quality recommendations, that the best recommendations that could be put forward are actually put forward, and that the combination of recommenders performs better than any constituent recommende

Gender differences in the influence of food safety and health concerns on dietary and physical activity habits

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The relationships between eating habits, smoking and alcohol consumption, and body mass index among baby boomers

The study was to examine the eating habits of baby boomers and to investigate the relationship of these and other lifestyle habits on their reported body mass indices (BMI). A questionnaire was administered by mail to a random sample of people aged 40 years and above, drawn from the Electoral Rolls in Victoria, Australia. Part of the questionnaire contained questions about the respondents’ eating habits, smoking status and alcohol use, as well as self reported heights and weights and demographic characteristics. Eight hundred and forty-four people (out of 1470) returned usable questionnaires. Statistically significant differences were found between the eating habits of men and women. Generally, more women snacked on high energy dense foods (e.g., confectionery). More men took larger mouthfuls than women. The eating habits of women appeared to be more formal than men’s. Four constructs named: unconstrained eating, traditional eating style, gulping, and chocolate and junk food were derived from the eating behaviour literature. Structural equation modelling showed that eating behaviour was associated with BMI along with current smoking, ex-smoking status, alcohol consumption, and demographics. Eating habits and other lifestyle behaviours appear to be associated with BMI though in different pathways for men and women

Factors Impacting Housing Tenure Choice of Canadian Young Adults

Deteriorating housing affordability is a pressing issue in Canada. Whereas there was a sustained housing market correction in the United States after the 2008 global financial crisis, the price of housing in major Canadian markets has since continued to reach record highs. Under the current neoliberal system, housing tenure critically impacts wealth trajectories. A lack of housing affordability in an asset-based welfare system that is mainly dependent on homeownership is very concerning. Young adults are the most disadvantaged by this issue as this age group enters into the lifecycle stage that has traditionally been marked by first-time entry into homeownership. This thesis aims to better understand the factors impacting tenure choice of Canadian young adult (25-34) households in order to inform public policy which will improve the future welfare prospects of this generation. A cross-sectional tenure choice study is first conducted through identical individual logistic regression models for the years 1999 and 2012 using data from the Statistics Canada Survey of Financial Security. The predictors of tenure choice included in the models are age, household type, number of earners, educational attainment, market income, liquid wealth, student loans, and region. The logit models estimate the effects of these socio-demographic and economic household factors on homeownership in 1999 and in 2012. Housing policy forces influencing household tenure choice cannot be quantitatively approximated in the models, but past literature has stressed their importance. Thus, the effects of policy changes over time are analyzed through the differences between the results of the tenure choice models for the two years. Additionally, an interaction model is used to test whether these differences over time are statistically significant. This tenure choice study shows that young adult households generally choose to enter homeownership if they are financially capable of doing so. However, the impact of rising housing prices is evident in the characteristics of young adult homeowners. Having a higher odds of homeownership in 2012 requires households to have an older major income earner, more earners in the household, higher educational attainment, and higher income. This also means that higher numbers of households are 'locked-out' of homeownership. In addition to mortgages, non-mortgage debt has a larger role in financing young adult homeownership over time. However, relatively smaller flexible asset buffers put these households at great financial risk of delinquency. This study also provides quantitative evidence that student loan debt decreases the odds of homeownership. More detailed explanations of these results are discussed as well as their policy implications