Trading Strategies and Market Microstructure: Evidence from a Prediction Market

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David Rothschild
Rajiv Sethi


We examine transaction-level data from Intrade's 2012 presidential winner market for the entire two-year period for which trading occurred. The data allow us to compute key statistics, including volume, transactions, aggression, directional exposure, holding duration, margin, and profit for each of 6,300 unique trader accounts. We identify a diverse set of trading strategies that constitute a rich market ecology. These range from arbitrage-based strategies with low and fleeting directional exposure to strategies involving large accumulated positions in one of the two major party candidates. Most traders who make directional bets do so consistently in a single direction, unlike the information traders in some canonical models of market microstructure. We present evidence suggestive of manipulation by a single large trader, and consider the possible motives for such behavior. Broader implications for the interpretation of prices in financial markets and the theory of market microstructure are drawn.

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Danielle Acker, Prediction Markets: Reality and Theory. Unpublished Manuscript, University of Bristol, 2016.

Randall E. Adkins and Andrews J. Dowdle. The money primary: What influences the outcome of preprimary presidential nomination fundraising? Presidential Studies Quarterly, 32(2):256–275, 2002.

Stephen Ansolabehere and Shanto Iyengar. Of horseshoes and horse races: Experimental studies of the impact of poll results on electoral behavior. Political Communication, 4(413-430), 1994.

Matthew Baron, Jonathan Brogaard, and Andrei Kirilenko. The trading profits of high frequency traders. Unpublished Manuscript, 2012.

Larry M. Bartels. Expectations and preferences in presidential nominating campaigns. American Political Science Review, 79(3):804–815, 1985.

Joyce Berg, Robert Forsythe, Forrest Nelson, and Thomas Rietz. Results from a dozen years of election futures markets research. In Handbook of Experimental Economics Results, Volume 1, 2008.

Andre Blais, Elisabeth Gidengil, and Neil Nevitte. Do polls influence the vote? In Richard G. C. Johnston and Henry E. Brady, editors, Capturing Campaign Effects, pages 263–279. University of Michigan Press, 2006.

Thomas E. Copeland and Dan Galai. Information effects on the bid-ask spread. Journal of Finance, 38(5):1457–1469, 1983.

Ester R. Fuchs, E. Scott Adler, and Lincoln A. Mitchell. Win, place, show: Public opinion polls and campaign contributions in a New York City election. Urban Affairs Review, 35(4):479–501, 2000.

John Geanakoplos. The leverage cycle. In NBER Macroeconomics Annual 2009. University of Chicago Press, 2010.

Lawrence R. Glosten and Paul R. Milgrom. Bid, ask and transaction prices in a specialist market with heterogeneously informed traders. Journal of Financial Economics, 14:71–100, 1985.

Donald Granberg and Edward Brent. When prophecy bends: The preference–expectation link in us presidential elections, 1952–1980. Journal of Personality and Social Psychology, 45(3):477, 1983.

Sanford J. Grossman and Joseph E. Stiglitz. On the impossibility of informationally efficient markets. American Economic Review, 70(3):393–408, 1980.

Milton Harris and Artur Raviv. Differences of opinion make a horse race. Review of Financial Studies, 6(3):473–506, 1993.

J. Michael Harrison and David M. Kreps. Speculative investor behavior in a stock market with heterogeneous expectations. Quarterly Journal of Economics, 92(2):323–336, 1978.

Martin F. Hellwig. On the aggregation of information in competitive markets. Journal of Economic Theory, 22:477–498, 1980.

Harrison Hong, Jose Scheinkman, and Wei Xiong. Asset float and speculative bubbles. Journal of Finance, 61(3):1073–1117, 2006.

Eugene Kandel and Neil D Pearson. Differential interpretation of public signals and trade in speculative markets. Journal of Political Economy, 103(4):831–872, 1995.

Willemien Kets, David M. Pennock, Rajiv Sethi, and Nisarg Shah. Betting strategies, market selection, and the wisdom of crowds. In Twenty-Eighth AAAI Conference on Artificial Intelligence, 2014.

Andrei A. Kirilenko, Albert S. Kyle, Mehrdad Samadi, and Tugkan Tuzun. The flash crash: The impact of high frequency trading on an electronic market. Available at SSRN:, 2011.

Brian Knight. Are policy platforms capitalized into equity prices? evidence from the bush/gore 2000 presidential election. Journal of Public Economics, 90(4–5):751–773, 2006.

Albert S Kyle. Continuous auctions and insider trading. Econometrica, 53(6):1315–1335, 1985.

Andrew Leigh and Justin Wolfers. Competing approaches to forecasting elections: Economic models, opinion polling and prediction markets. Economic Record, 82(258):325–340, 2006.

Catherine Marsh. Back on the bandwagon: The effect of opinion polls on public opinion. British Journal of Political Science, 15(1):51–74, 1985.

Paul Milgrom and Nancy Stokey. Information, trade and common knowledge. Journal of Economic Theory, 26(1):17–27, 1982.

Edward M Miller. Risk, uncertainty, and divergence of opinion. Journal of Finance, 32(4):1151– 1168, 1977.

Diana C Mutz. Effects of horse-race coverage on campaign coffers: Strategic contributing in presidential primaries. Journal of Politics, 57(4):1015–1042, 1995.

Richard Nadeau, Edouard Cloutier, and J-H. Guay. New evidence about the existence of a bandwagon effect in the opinion formation process. International Political Science Review, 14(2): 203–213, 1993.

Nathaniel Popper. Which changed first, the polls or the markets? New York Times, October 16 2012.

Paul W. Rhode and Koleman S. Strumpf. Manipulating political stock markets: A field experiment and a century of observational data. Working Paper, University of Arizona, 2008.

David Rothschild. Forecasting elections comparing prediction markets, polls, and their biases. Public Opinion Quarterly, 73(5):895–916, 2009.

David Rothschild. Combining forecasts for elections: Accurate, relevant, and timely. International Journal of Forecasting, 31(3): 952-964, 2014.

David Rothschild and Neil Malhotra. Are public opinion polls self-fulfilling prophecies? Research & Politics, 1(2):1–10, 2014.

David Rothschild and David M Pennock. The extent of price misalignment in prediction markets. Algorithmic Finance, 3(1):3–20, 2014.

Jose Scheinkman and Wei Xiong. Overconfidence and speculative bubbles. Journal of Political Economy, 111(6):1183–1219, 2003.

Rajiv Sethi and Muhamet Yildiz. Public disagreement. American Economic Journal:

Microeconomics, 4(3):57–95, 2012.

Alp Simsek. Belief disagreements and collateral constraints. Econometrica, 81(1):1–53, 2013.

Andrew Skalaban. Do the polls affect elections? some 1980 evidence. Political Behavior, 10(2): 136–150, 1988.

Erik Snowberg, Justin Wolfers, and Eric Zitzewitz. Partisan impacts on the economy: evidence from prediction markets and close elections. Quarterly Journal of Economics, 122(2):807–829, 2007.

Derek Thompson. Should presidential campaigns spend more money manipulating intrade? The Atlantic, October 23 2012.

Carole Jean Uhlaner and Bernard Grofman. The race may be close but my horse is going to win: Wish fulfillment in the 1980 presidential election. Political Behavior, 8(2):101–129, 1986.

Tom W. G. van der Meer, Armen Hakhverdian, and Loes Aaldering. Off the fence, onto the bandwagon? a large-scale survey experiment on effect of real-life poll outcomes on subsequent vote intentions. International Journal of Public Opinion Research, 28(1): 46-72, 2016.

Justin Wolfers and Andrew Leigh. Three tools for forecasting federal elections: Lessons from 2001. Australian Journal of Political Science, 37(2):223–240, 2002.