certifier can enable the seller to disclose her private information publicly, as well as gather additional market information …-maximal information-gathering. Thus, optimal contracts eliminate private information but not market uncertainty; even though the latter … would be costless, it is suboptimal as it requires excessive information rents to the seller. Thus, market inefficiencies …

This paper studies a principal-agent relation in which the principal's private information about the agent's effort … and not on the public signal. Nonetheless, public information is valuable as it facilitates truthful subjective evaluation …