The Social Value of Financial Expertise

Abstract

I study expertise acquisition in a model of trading under asymmetric information. I propose and implement a method to measure r, the ratio of the marginal social value to the marginal private value of expertise. This can be decomposed into three sufficient statistics: traders’ average profits, the fraction of bad assets among traded assets, and the elasticity of good assets traded with respect to capital inflows. I measure r = 0.16 for the junk bond underwriting market. Since this is less than 1, it implies that marginal investments in expertise destroy surplus. (JEL D82, G11, G14, G21, L84)