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Informed Trading, Investment, and Welfare

James Dow and Rohit Rahi
The Journal of Business
Vol. 76, No. 3 (July 2003), pp. 439-454
DOI: 10.1086/375254
Stable URL:
Page Count: 16
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This article studies the welfare economics of informed stock market trading. We analyze the effect of more informative prices on investment, given that this dependence will itself be reflected in equilibrium prices. While a higher incidence of informed speculation always increases firm value through a more informative trading process, the effect on agents’ welfare depends on how revelation of information changes risk‐sharing opportunities in the market. Greater revelation of information that agents wish to insure against reduces their hedging opportunities. On the other hand, early revelation of information that is uncorrelated with hedging needs allows agents to construct better hedges.

Notes and References

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