Informational efficiency and welfare. (English) Zbl 1498.91412

Bernardinelli, Luca; Guasoni, Paolo; Mayerhofer, Eberhard

Math. Financ. Econ. 16, No. 4, 659-683 (2022).

Summary: In a continuous-time market with a safe rate and a risky asset that pays a dividend stream depending on a latent state of the economy, several agents make consumption and investment decisions based on public information-prices and dividends-and private signals. If each investor has constant absolute risk aversion, equilibrium prices do not reveal all the private signals, but lead to the same estimate of the state of the economy that one would hypothetically obtain from the knowledge of all private signals. Accurate information leads to low volatility, ostensibly improving market efficiency, but also reduces each agent’s consumption through a decrease in the price of risk. Thus, informational efficiency is reached at the expense of agents’ welfare.

MSC:

91G15

Financial markets

Keywords:

equilibrium; rational expectations; heterogeneous information; welfare

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