On changes of measure in stochastic volatility models
Bernard Wong
School of Actuarial Studies, University of New South Wales, Sydney 2152, Australia
Search for more papers by this authorC. C. Heyde
Mathematical Sciences Institute, The Australian National University, Canberra 0200, Australia
Department of Statistics, Columbia University, New York 10027, USA
Search for more papers by this authorBernard Wong
School of Actuarial Studies, University of New South Wales, Sydney 2152, Australia
Search for more papers by this authorC. C. Heyde
Mathematical Sciences Institute, The Australian National University, Canberra 0200, Australia
Department of Statistics, Columbia University, New York 10027, USA
Search for more papers by this authorAbstract
Pricing in mathematical finance often involves taking expected values under different equivalent measures. Fundamentally, one needs to first ensure the existence of ELMM, which in turn requires that the stochastic exponential of the market price of risk process be a true martingale. In general, however, this condition can be hard to validate, especially in stochastic volatility models. This had led many researchers to “assume the condition away,” even though the condition is not innocuous, and nonsensical results can occur if it is in fact not satisfied. We provide an applicable theorem to check the conditions for a general class of Markovian stochastic volatility models. As an example we will also provide a detailed analysis of the Stein and Stein and Heston stochastic volatility models.
References
- 1
Ball and
Roma, Stochastic volatility option pricing, Journal of Financial and Quantitative Analysis. (1994) 29, no. 4, 584–607, https://doi.org/10.2307/2331111.
10.2307/2331111 Google Scholar
- 2
Bibby and
Sørensen, A hyperbolic diffusion model for stock prices, Finance and Stochastics. (1997) 1, no. 1, 25–41, https://doi.org/10.1007/s007800050015.
10.1007/s007800050015 Google Scholar
- 3 Chernov and Ghysels, A study towards a unified approach to the joint estimation of objective and risk neutral measures for the purpose of options valuation, Journal of Financial Economics. (2000) 56, no. 3, 407–458, https://doi.org/10.1016/S0304-405X(00)00046-5.
- 4 Cox A. M. G. and Hobson D. G., Local martingales, bubbles and option prices, Finance and Stochastics. (2005) 9, no. 4, 477–492, https://doi.org/10.1007/s00780-005-0162-y.
- 5 Cox J. C., Ingersoll Jr. J. E., and Ross S. A., A theory of the term structure of interest rates, Econometrica. (1985) 53, no. 2, 385–408, https://doi.org/10.2307/1911242.
- 6 Dai and Singleton, Specification analysis of affine term structure models, Journal of Finance. (2000) 55, no. 5, 1943–1978, https://doi.org/10.1111/0022-1082.00278.
- 7 Delbaen and Schachermayer, A general version of the fundamental theorem of asset pricing, Mathematische Annalen. (1994) 300, no. 3, 463–520, https://doi.org/10.1007/BF01450498.
- 8 Delbaen and Schachermayer, The existence of absolutely continuous local martingale measures, The Annals of Applied Probability. (1995) 5, no. 4, 926–945.
- 9
Delbaen and
Schachermayer, The no-arbitrage property under a change of numéraire, Stochastics and Stochastics Reports. (1995) 53, no. 3-4, 213–226.
10.1080/17442509508833989 Google Scholar
- 10 Duffee, Term premia and interest rate forecasts in affine models, Journal of Finance. (2002) 57, no. 1, 405–443, https://doi.org/10.1111/1540-6261.00426.
- 11 Feller, Two singular diffusion problems, Annals of Mathematics. Second Series. (1951) 54, 173–182.
- 12 Frey, Derivative asset analysis in models with level-dependent and stochastic volatility, CWI Quarterly. (1997) 10, no. 1, 1–34.
- 13 Friedman, Partial Differential Equations of Parabolic Type, 1964, Prentice-Hall, New Jersey.
- 14 Geman, El Karoui, and Rochet, Changes of numéraire, changes of probability measure and option pricing, Journal of Applied Probability. (1995) 32, no. 2, 443–458, https://doi.org/10.2307/3215299.
- 15 Heath, Platen, and Schweizer, A comparison of two quadratic approaches to hedging in incomplete markets, Mathematical Finance. (2001) 11, no. 4, 385–413, https://doi.org/10.1111/1467-9965.00122.
- 16 Heath and Schweizer, Martingales versus PDEs in finance: an equivalence result with examples, Journal of Applied Probability. (2000) 37, no. 4, 947–957, https://doi.org/10.1239/jap/1014843075.
- 17 Henderson, Analytical comparisons of option prices in stochastic volatility models, Mathematical Finance. (2005) 15, no. 1, 49–59, https://doi.org/10.1111/j.0960-1627.2005.00210.x.
- 18 Heston, A closed form solution for options with stochastic volatility with applications to bond and currency options, Review of Financial Studies. (1993) 6, no. 2, 327–344, https://doi.org/10.1093/rfs/6.2.327.
- 19 Hoffman, Platen, and Schweizer, Option pricing under incompleteness and stochastic volatility, Mathematical Finance. (1992) 2, 153–187.
- 20 Hull and White, The pricing of options on assets with stochastic volatilities, Journal of Finance. (1987) 42, no. 2, 281–300, https://doi.org/10.2307/2328253.
- 21 Johnson and Helms L. L., Class D supermartingales, Bulletin of the American Mathematical Society. (1963) 69, 59–62.
- 22 Karatzas and Shreve S. E., Brownian Motion and Stochastic Calculus, 1988, Springer, New York, 113, Graduate Texts in Mathematics.
- 23 Lewis A. L., Option Valuation under Stochastic Volatility, 2000, Finance Press, California.
- 24 Pitman and Yor, A decomposition of Bessel bridges, Zeitschrift für Wahrscheinlichkeitstheorie und Verwandte Gebiete. (1982) 59, no. 4, 425–457.
- 25 Revuz and Yor, Continuous Martingales and Brownian Motion, 1991, Springer, Berlin, 293, Fundamental Principles of Mathematical Sciences.
- 26 Rogers L. C. G. and Williams, Diffusions, Markov Processes, and Martingales. Vol. 2, 2000, 2nd edition, Cambridge University Press, Cambridge, Cambridge Mathematical Library, originally published by Wiley, Chichester, 1987.
- 27
Rydberg, A note on the existence of equivalent martingale measures in a Markovian setting, Finance and Stochastics. (1997) 1, no. 3, 251–257, https://doi.org/10.1007/s007800050024.
10.1007/s007800050024 Google Scholar
- 28 Rydberg T. H., Generalized hyperbolic diffusion processes with applications in finance, Mathematical Finance. (1999) 9, no. 2, 183–201, https://doi.org/10.1111/1467-9965.00067.
- 29
Schöbel and
Zhu, Stochastic volatility with an Ornstein-Uhlenbeck process: an extension, European Finance Review. (1999) 3, no. 1, 23–46, https://doi.org/10.2139/ssrn.100831.
10.2139/ssrn.100831 Google Scholar
- 30 Sin C. A., Complications with stochastic volatility models, Advances in Applied Probability. (1998) 30, no. 1, 256–268, https://doi.org/10.1239/aap/1035228003.
- 31 Stein and Stein, Stock price distributions with stochastic volatility: an analytic approach, Review of Financial Studies. (1991) 4, no. 4, 727–752, https://doi.org/10.1093/rfs/4.4.727.
- 32 Wong and Heyde C. C., On the martingale property of stochastic exponentials, Journal of Applied Probability. (2004) 41, no. 3, 654–664, https://doi.org/10.1239/jap/1091543416.