Discussion paper

DP9201 Vague Lies: How to Advise Consumers When They Complain

This paper analyzes the incentives of a seller to provide (un)biased and (im)precise advice about a complex product such as insurance, banking and telecommunication services. Misleading the buyers by biasing the advice upwards increases the revenues but also the expected fine imposed by the authority. Making the advice less precise does not affect the revenues in equilibrium but interferes with the authority's inference and affects the expected fine in a non-monotonic way. In particular, making the advice less precise makes it harder to convict the seller but increases the expected fine when the seller is found guilty. We find that, in the equilibrium, biasing the advice and making it noisier are complements; in particular, a higher buyers' heterogeneity, a stricter standard of proof employed by the authority and a larger share of credulous consumers make the advice more biased and less precise.


Drugov, M and M Troya Martinez (2012), ‘DP9201 Vague Lies: How to Advise Consumers When They Complain‘, CEPR Discussion Paper No. 9201. CEPR Press, Paris & London. https://cepr.org/publications/dp9201