Anastasia PARAKHONYAK soutiendra sa thèse de doctorat en sciences économiques le jeudi 24 mai 2018 à 10h00, Salle MQ 212 (Manufacture des Tabacs) sur le sujet «Essays on Economics of Information : Search, Network, Price Discrimination ».
Directeur de thèse: Bruno JULLIEN
Directeur de Recherche, CNRS, Toulouse School of Economics
Le jury sera composé de :
- M. Markus REISINGER, Professeur, Frankfurt School of Finance and Management
- M. Thibaud VERGE, Professeur, ENSAE
- M. Bruno JULLIEN, Professeur, Toulouse School of Economics
- M. Patrick REY, Professeur, Université Toulouse Capitole
Résumé (en anglais)
This thesis consists of three independent chapters addressing different questions of information economics.
The first chapter studies optimal strategies of firms which are present in both offline and online markets. We study optimal pricing strategies of retailers in presence of showrooming and their decisions on distribution channels. Showrooming is a situation where consumers try products at brick-and-mortar stores before purchasing them online at a lower price. One way to prevent showrooming is to use a price matching policy, whereby price is the same in both the physical store and the online channel. We show that for small search costs, a price matching policy is indeed optimal. However for higher search costs price matching is suboptimal, and online and offline purchases coexist with showrooming. A firm which faces online competition from a foreign multichannel retailer has an incentive to geo-block, i.e. refuse to serve foreign customers, even though it leads to a decrease in potential demand. Geo-blocking relaxes online competition and leads to higher prices both online and in brick-and-mortar stores. A legal price parity requirement helps to eliminate incentives to geo-block and thus restores online competition.
The second chapter analyzes information diffusion process in communication networks where social interactions are costly. We provide a dynamic model with strategic agents who decide how much effort to put into the propagation of information about a product in each period. We show that the equilibrium level of the individual communication effort is convex in the proportion of informed agents, and lower than the socially optimal level due to the substantial free-riding effect. We show that for sufficiently high recommendation cost it is socially optimal that symmetric agents exert the same communication effort while for low recommendation cost this is not true. In the context of our model we analyze the advertising strategy of the firm launching a new product with positive network externalities for consumers. The analysis shows that the outcome of advertisement is decreasing fast with the proportion of informed consumers due to the free-riding effect. Thus, optimally the firm has to adjust and reduce the level of advertising in each period.
The third chapter is a co-authored paper with Maarten Janssen and Alexei Parakhonyak.
In this paper we propose a new equilibrium concept of Non-reservation price equilibria (Non-RPE). Reservation price equilibria (RPE) do not accurately assess market power in consumer search markets. In most search markets, consumers do not know important elements of the environment in which they search (such as, for example, firms’ cost). We argue that when consumers learn when searching, RPE suffer from theoretical issues, such as non-existence and critical dependence on specific out-of-equilibrium beliefs. We characterize equilibria where consumers rationally choose search strategies that are not characterized by a reservation price. Non-RPE always exist and do not depend on specific out-of-equilibrium beliefs. Non-RPE have active consumer search and are consistent with recent empirical findings.
