Three essays on the economic analysis of consumer law.

Summary Consumers have bounded rationality and are subject to various cognitive biases. The thesis studies the consequences of rationality biases on consumer behavior and the implications for consumer policy. Each of the three chapters of the thesis is devoted to a particular bias (quality overestimation, utility anticipation errors, projection bias) in a given competitive context. The first two chapters are built on standard duopoly models to which rationality biases are incorporated: the first is a duopoly with horizontal differentiation inspired by Dixit (1979), while the second considers a vertical differentiation model adapted from Gabszewicz & Thisse (1979). The third chapter extends to three periods the projection bias model proposed by Loewenstein et al. (2003). I conclude that, while cognitive biases may lead to suboptimal choices in some cases (Chapters 1 and 2), naive consumers may also have an advantage over sophisticated agents (Chapter 3). This finding argues for a detailed and measured intervention in the market. Finally, policy recommendations are formulated: I advocate a renewed approach to consumer law, which would no longer be based primarily on consumer information but more on cognitive remedies. Examples of concrete measures are discussed throughout the thesis.