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Regulatory Medicine Against Financial Market Instability: What Helps And What Hurts?

  • Stefan Kerbl

Do we know if a short selling ban or a Tobin Tax result in more stable asset prices? Or do they in fact make things worse? Just like medicine regulatory measures in financial markets aim at improving an already complex system. And just like medicine these interventions can cause side effects which are even harder to assess when taking the interplay with other measures into account. In this paper an agent based stock market model is built that tries to find answers to the questions above. In a stepwise procedure regulatory measures are introduced and their implications on market liquidity and stability examined. Particularly, the effects of (i) a ban of short selling (ii) a mandatory risk limit, i.e. a Value-at-Risk limit, (iii) an introduction of a Tobin Tax, i.e. transaction tax on trading, and (iv) any arbitrary combination of the measures are observed and discussed. The model is set up to incorporate non-linear feedback effects of leverage and liquidity constraints leading to fire sales and escape dynamics. In its unregulated version the model outcome is capable of reproducing stylised facts of asset returns like fat tails and clustered volatility. Introducing regulatory measures shows that only a mandatory risk limit is beneficial from every perspective, while a short selling ban - though reducing volatility - increases tail risk. The contrary holds true for a Tobin Tax: it reduces the occurrence of crashes but increases volatility. Furthermore, the interplay of measures is not negligible: measures block each other and a well chosen combination can mitigate unforeseen side effects. Concerning the Tobin Tax the findings indicate that an overdose can do severe harm.

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Paper provided by in its series Papers with number 1011.6284.

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Date of creation: Nov 2010
Date of revision: Nov 2010
Handle: RePEc:arx:papers:1011.6284
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  1. De Grauwe, Paul & Grimaldi, Marianna, 2006. "Exchange rate puzzles: A tale of switching attractors," European Economic Review, Elsevier, vol. 50(1), pages 1-33, January.
  2. Damien Challet & Matteo Marsili & Yi-Cheng Zhang, 2001. "Stylized facts of financial markets and market crashes in Minority Games," Papers cond-mat/0101326,
  3. G. Ehrenstein & F. Westerhoff & D. Stauffer, 2005. "Tobin tax and market depth," Quantitative Finance, Taylor & Francis Journals, vol. 5(2), pages 213-218.
  4. Paolo Pellizzari & Frank Westerhoff, 2009. "Some effects of transaction taxes under different microstructures," Post-Print hal-00727590, HAL.
  5. Mannaro, Katiuscia & Marchesi, Michele & Setzu, Alessio, 2008. "Using an artificial financial market for assessing the impact of Tobin-like transaction taxes," Journal of Economic Behavior & Organization, Elsevier, vol. 67(2), pages 445-462, August.
  6. Friedman, Daniel & Abraham, Ralph, 2009. "Bubbles and crashes: Gradient dynamics in financial markets," Journal of Economic Dynamics and Control, Elsevier, vol. 33(4), pages 922-937, April.
  7. Lux, Thomas, 1998. "The socio-economic dynamics of speculative markets: interacting agents, chaos, and the fat tails of return distributions," Journal of Economic Behavior & Organization, Elsevier, vol. 33(2), pages 143-165, January.
  8. Frank Westerhoff, 2002. "Heterogeneous Traders and the Tobin Tax," Computing in Economics and Finance 2002 51, Society for Computational Economics.
  9. James Tobin, 1978. "A Proposal for International Monetary Reform," Cowles Foundation Discussion Papers 506, Cowles Foundation for Research in Economics, Yale University.
  10. Hanke, Michael & Huber, Jürgen & Kirchler, Michael & Sutter, Matthias, 2010. "The economic consequences of a Tobin tax--An experimental analysis," Journal of Economic Behavior & Organization, Elsevier, vol. 74(1-2), pages 58-71, May.
  11. B. LeBaron, 2001. "A builder's guide to agent-based financial markets," Quantitative Finance, Taylor & Francis Journals, vol. 1(2), pages 254-261.
  12. R. Cont, 2001. "Empirical properties of asset returns: stylized facts and statistical issues," Quantitative Finance, Taylor & Francis Journals, vol. 1(2), pages 223-236.
  13. J. B. Satinover & D. Sornette, 2007. "”Illusion of control” in Time-Horizon Minority and Parrondo Games," The European Physical Journal B - Condensed Matter and Complex Systems, Springer, vol. 60(3), pages 369-384, December.
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