<p>In this dissertation, I discuss two important factors in individuals' decision-making processes: subjective expectation bias and time-inconsistent preferences. In Chapter I, I look at how individuals' own subjective expectations about certain future events are different from what actually happens in the future, even after controlling for individuals' private information. This difference, which is defined as the expectation bias in this paper, is found to have important influence on individuals' choices. Specifically, I look into the relationship between US elderly's subjective longevity expectation biases and their smoking choices. I find that US elderly tend to over-emphasize the importance of their genetic makeup but underestimate the influence of their health-related choices, such as smoking, on their longevity. This finding can partially explain why even though US elderly are found to be more concerned with their health and more forward-looking than we would have concluded using a model which does not allow for subjective expectation bias, we still observe many smokers. The policy simulation further confirms that if certain public policies can be designed to correct individuals' expectation biases about the effects of their genes and health-related choices on their longevity, then the average smoking rate for the age group analyzed in this paper will go down by about 4%.</p><p>In Chapter II, my co-author, Hanming Fang, and I look at one possible explanation to the under-utilization of preventive health care in the United States: procrastination. Procrastination, the phenomenon that individuals postpone certain decisions which incur instantaneous costs but bring long-term benefits, is captured in economics by hyperbolic discount factors and the corresponding time-inconsistent preferences. This chapter extends the semi-parametric identification and estimation method for dynamic discrete choice models using Hotz and Miller's (1993) conditional choice probability approach to the setting where individuals may have hyperbolic discounting time preferences and may be naive about their time inconsistency. We implement the proposed estimation method to US adult women's decisions of undertaking mammography tests to evaluate the importance of present bias and naivety in the under-utilization of mammography, controlling for other potentially important explanatory factors such as age, race, household income, and marital status. Preliminary results show evidence for both present bias and naivety in adult women's decisions of undertaking mammography tests. Using the parameters estimated, we further conduct some policy simulations to quantify the effects of the present bias and naivety on the utilization of preventive health care in the US.</p> / Dissertation

Les jeux vidéo violents sont considérés comme un facteur favorisant les violences. Un consensus relativement large est aujourd'hui partagé par une majorité des chercheurs. Une nouvelle génération de travaux doit désormais travailler à déterminer 1. s'il existe des profils plus exposés de joueurs 2. par quels mécanismes causaux les jeux violents augmentent les conduites d'agression. A travers 6 études comprenant une recherche transversale et cinq recherches expérimentales, nous apportons un éclairage nouveau concernant les modulateurs et les médiateurs des effets des jeux vidéo violents sur l'agression humaine. / Violent video games are considered as a risk factor for violence. A fairly broad consensus today is shared among the majority of researchers. A new generation of research must now work to determine 1. if there are more at risk player profiles 2. causal mechanisms by which violent video games increase aggressive behavior. Through six studies including a cross-sectional research and five experimental research studies, we provide a new perspective on the mediators and moderators of violent video game effects on human aggression.

As increasing emphasis is being placed on student college and career readiness, instructional approaches seek to develop content and skill proficiency. I gathered student perspectives on teacher expectations and instructional opportunities in core content classes in order to determine if expectation bias influences college readiness preparation in the classroom. Student academic self-concept and college readiness were examined alongside beliefs about teacher expectations and instructional opportunities in a conceptual framework for student perceptions. In this qualitative study, I utilized four focus groups of high school students from two cohorts to analyze perceptions across students from mostly on-level core classes and those from mostly advanced core classes. Findings showed students held high expectations of their own current and future performance, as well as perceived teachers generally hold high expectations, though this was shown through the development of relational capacity rather than instructional opportunities to develop college readiness skills or connect to students' future ambitions. The results of the study provide insight to educators seeking to create stronger connections for students between current educational experiences and future postsecondary opportunities.