Title: Essays in applied game theory
Description: The loose unifying aim of my dissertation is to better understand ethical norms. Ethical norms in these essays are shared expectations about how people behave in social interactions. Each essay analyzes aspects of a particular norm--honest and informative speech, respect for property, or altruism--using tools drawn from game theory. The first essay, on vagueness and deceptive speech, shows that when speakers try to deceive listeners by exploiting the mistakes that some listeners make, then weak levels of honesty can lead to dramatically different communication than when communication is between self-interested agents. Honesty leads senders to prefer vague lies that they believe will be successful, so that equivocation becomes distrusted by more sophisticated listeners. The second essay, on the stability of conventions in Hawk-Dove games, shows that informal property rights could arise because of the nature of the ownership relation when several people can simultaneously compete over the same object. This particular norm about possessions will be more stable than other norms if it develops in the presence of persistent but unlikely mistakes in behavior.

For a given possession, only one person controls that object, but many people might want to take control of it. Non-owners must compete with other non-owners to take control, but owners do not have to compete with the owners of other objects to maintain control. The third essay, on evaluating particularism, looks at a classic public-goods problem--free-riding--that can arise when people are altruistic but place greater weight on themselves than others. When altruists care about particular people more than other people in general, the altruists' sharpened focus reduces the benefit of free-riding on other altruists. The essay uses game theory to examine how external factors shape the degree to which particularism solves the free-riding problem when imperfect altruistic preferences are taken as a given.