AN EXAMINATION OF PREDICTION MARKET EFFICIENCY: NBA CONTRACTS ON TRADESPORTS

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Published: Dec 17, 2012
DOI: https://doi.org/10.5750/jpm.v3i2.462

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Richard Borghesi
University of South Florida Department of Finance

Abstract

In this paper I examine the absolute and relative price efficiency of NBA options listed on Tradesports.com.  I find that contracts within specific price bands are misvalued, but also demonstrate that this market is more efficient than is the market for NFL options.  Specifically, I show that contracts priced around $25 win (expire at $100) at a rate less than expected, while those priced around $75 win at a rate greater than expected.  The magnitudes of these deviations between prices and fundamental values are less than those in the NFL market.  Also, while prior theoretical work predicts that low-priced contracts should be overpriced, I instead find that NBA contracts priced near $2.50 win more frequently than expected.I thank Rob Dougherty and Brijesh Patel for assistance with the NBA event data, and Leighton Vaughan Williams for meaningful suggestions throughout.  Any errors are strictly my own.

Article Details

Issue
Vol. 3 No. 2 (2009)
Section
Articles

References

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