Interactions between players with private information and opposed interests are often prone to bad advice and inefficient outcomes, e.g. markets for financial or health care services. In a deception game we investigate experimentally which factors could improve advice quality. Besides advisor competition and identifiability, we add the possibility for clients to make a voluntary payment, a bonus, after observing advice quality. While the combination of competition and reputation concerns achieves the highest rate of truthful advice, we observe a similar effect, when the bonus is combined with one of them. Thus, our results suggest that a voluntary component can act as a substitute for either competition or reputation, decreasing moral hazard.
asymmetric information principal-agent expert services deception game sender-receiver game reciprocity reputation experiments voluntary payment competition