Cheap talk

In game theory, cheap talk is communication between players that does not directly affect the payoffs of the game. Providing and receiving information is free. This is in contrast to signalling, in which sending certain messages may be costly for the sender depending on the state of the world.

This basic setting set by Vincent Crawford and Joel Sobel[1] has given rise to a variety of variants.

To give a formal definition, cheap talk is communication that is:[2]

  1. costless to transmit and receive
  2. non-binding (i.e. does not limit strategic choices by either party)
  3. unverifiable (i.e. cannot be verified by a third party like a court)

Therefore, an agent engaging in cheap talk could lie with impunity, but may choose in equilibrium not to do so.

  1. ^ Crawford, Vincent P.; Sobel, Joel (November 1982). "Strategic Information Transmission". Econometrica. 50 (6): 1431–1451. CiteSeerX 10.1.1.295.3462. doi:10.2307/1913390. JSTOR 1913390.
  2. ^ Farrell, Joseph (1987). "Cheap Talk, Coordination, and Entry". The RAND Journal of Economics. 18 (1): 34–39. JSTOR 2555533.