Three Essays on Trading Behavior

This dissertation analyzes trading behavior in financial markets from multiple perspectives. In chapter 1, "Exploratory Trading," I investigate the mechanisms underlying high-frequency traders' capacity to profitably anticipate price movements. I develop a model of how a trader could gather valuable private information by using her own orders in an exploratory manner to learn about market conditions. The model's predictions are borne out empirically, and I find that this "exploratory trading" model helps to resolve several central open questions about high-frequency trading. Chapters 2 and 3 focus on the trading behavior of individuals. Chapter 2, "Foundations of the Disposition Effect: Experimental Evidence," (co-authored with Johanna Mollerstrom), presents and analyzes results from a laboratory experiment intended to examine if and how "regret aversion"--aversion to admitting mistakes--affects people's trading decisions. Although the experimental results resolve little about regret aversion specifically, they reveal some novel and unexpected effects, most importantly that subjects radically changed their trading decisions when they were compelled to devote a minimal amount of extra attention. In chapter 3, "Price Targets," I analyze how rational investors who privately observe information of indeterminate quality use prices to learn about whether or not their private information is valuable. I derive implications about trading behavior that not only help to explain a variety of empirical puzzles, but also generate several new testable predictions. Although these three essays differ considerably in methodology and focus, they all address the same basic issue of understanding the foundations of trading behavior.