22 juin HDR d'Andrew RHODES

22 Juin 2020 Recherche

Andrew RHODES, assistant professeur à l'univeristé Toulouse 1 Capitole, soutiendra ses travaux pour l’ H.D.R. en Sciences économiques le lundi 22/06/2020 à 15h30.

Titre "Essays on Multiproduct Firms and Consumer Search

Soutenance via Zoom Meeting. Pour y participer, merci de contacter Wilfried Sand-Zantman.

Les membres du jury :

  • Bruno JULLIEN, Directeur de recherche, CNRS – TSE
  • Jeanine MIKLOS-THAL, Université de Rochester, USA
  • Régis Renault, Université de Cergy
  • Volker NOCKE, Université de Mannheim 
  • Wilfried ZAND-ZANTMAN, Université Toulouse 1 Capitole – TSE

Résumé (en anglais):

This body of work looks at both the behavior of multiproduct firms and the impact of search frictions on market outcomes. Chapters 1 and 2 consider multiproduct mergers. Chapter 1 studies remedies when the merging firms are active in several different product (or geographic) markets. It shows that under certain conditions, a policymaker interested in maximizing aggregate consumer surplus should implement many remedies in a small number of markets. Chapter 2 demonstrates that when products are vertically differentiated, many well-known results from the extant merger literature are not robust. As one example, consumer surplus can increase when a merger generates no synergies. In Chapter 3 consumers wish to buy a product repeatedly over time, but have to search for information about prices and match values. As firms become older they optimally raise their price, which generates consumer turnover because some consumers who were previously loyal stop buying and search for a new product. Chapter 4 considers markets where consumers find it hard to judge product quality, and allows for the possibility that firms may make false claims about their quality. One result is that, under certain conditions, consumers are best off with a laissez-faire policy which permits a positive level of false advertising. Chapters 5-7 look at the behavior of multiproduct firms in markets with search frictions. Chapter 5 shows, amongst other things, that a low advertised price on one product can credibly convince consumers that other (unadvertised) prices are lower, making it more attractive for them to search the firm. Chapter 6 meanwhile allows sellers of unrelated products to merge and thereby save consumers some search costs. It finds that when search costs are high the equilibrium market structure has only large firms, but when search costs are small the equilibrium market structure is asymmetric with a mix of large and small firms. Finally, chapter 7 considers the optimal product range of a multiproduct intermediary. It shows how all relevant demand and cost information on a product can be reduced to a two-dimensional sufficient statistic. It then characterizes which products should be stocked (and whether this should be done exclusively or non-exclusively) as a function of (the distribution of) that sufficient statistic.