Working Paper: CEPR ID: DP9785
Authors: Kyungmin Kim; Philipp Kircher
Abstract: We consider a frictional two-sided matching market in which one side uses public cheap-talk announcements so as to attract the other side. We show that if the first-price auction is adopted as the trading protocol, then cheap talk can be perfectly informative, and the resulting market outcome is efficient, constrained only by search frictions. We also show that the performance of an alternative trading protocol in the cheap-talk environment depends on the level of price dispersion generated by the protocol: If a trading protocol compresses (spreads) the distribution of prices relative to the first-price auction, then an efficient fully revealing equilibrium always (never) exists. Our results identify the settings in which cheap talk can serve as an efficient competitive instrument, in the sense that the central insights from the literature on competing auctions and competitive search continue to hold unaltered even without ex ante price commitment.
Keywords: cheap talk; commitment; competitive search; directed search
JEL Codes: C72; D82; D83
Edges that are evidenced by causal inference methods are in orange, and the rest are in light blue.
| Cause | Effect |
|---|---|
| cheap talk (C79) | market efficiency (G14) |
| first-price auction (D44) | cheap talk (C79) |
| first-price auction (D44) | efficient market outcomes (G14) |
| trading protocol (F13) | efficient fully revealing equilibrium (D51) |
| trading protocol (F13) | price dispersion (L11) |
| price dispersion (L11) | efficient fully revealing equilibrium (D51) |