Risk Evaluation of Banking Index with Volatility Estimation through Stochastic Volatility Model: A Semiparametric Bayesian Approach

Document Type : Research Paper

Authors

1 Assistant Prof., Faculty of Engineering, University of Science and Culture, Tehran, Iran

2 MSc. in Financial Engineering, University of Science and Culture, Tehran, Iran

Abstract

Estimation of the return distribution has a crucial role in Risk measurement and since the precision of risk measures depends on the precision of the return distribution, truly estimation of return distribution has attracted a huge attention. Although using Stochastic Volatility models with parametric assumptions for estimation and illustration of the volatilities has been common in research, these assumptions usually result in careless estimations. So in the following research a semiparametric approach has been used for estimation of the volatility by using a normal mixture dirichlet process. In this paper the distribution of the logarithm of the squared returns of banking index of Tehran Stock Exchange has been estimated by using mixtures of normal family and employing an MCMC algorithm. Finally, the results has been compared to the Basic stochastic volatility model. The results show that when the return distribution is skewed, estimates of volatility using the model can differ dramatically from those using a Normal return distribution. Furthermore, when return distribution is similar to a normal distribution, the results of this model are similar to the results of the parametric model.

Keywords

Main Subjects


Abanto-Valle, C., Bandyopadhyay, D., Lachos, V. & Enriquez, I. (2010). Robust Bayesian Analysis of Heavy-tailed Stochastic Volatility Models using Scale Mixtures of Normal Distributions. Computational Statistics and Data analysis, 54(12), 2883-2898.
Barndorff-Nielsen, E. (1997). Normal Inverse Gaussian Distribution and Stochastic Volatility Modelling. Scandinavian Journal of Statistics, 24 (1), 1-13.
Broto, C. & Ruiz, E. (2004). Estimation Methods for Stochastic Volatility Models: A Survey. Journal of Economic Survey, 18(5), 613-649.
Delatola, E.I. &  Griffin, J. (2011). Bayesian Nonparametric Modeling of the Return Distribution with Stochastic Volatility. Bayesian Analysis, 6 (4), 901-926.
Fuller, W. (1996). Introduction to Statistical Time Series (Second),JOHN WILEY,New York.
Griffin, J. (2010). Default Periors foe Density Estimation with Mixture Models. Bayesian Analysis, 1 (5), 45-64.
Jacquier, E., Polson, N. & Rossi, P. (1994). Bayesian Analysis of Stochastic Volatility Models. Journal of Business & Economic Statistics, 12 (4), 317-389.
Jacquier, E., Polson, N. & Rossi, P. (2003). Bayesian analysis of stochastic volatility models with fat-tails and correlated errors. Journal of Econometrics, 20.1 (2002): 69-87.
Jensen, M., & Maheu, J. (2010). Bayesian Semiparametric Stochastic Volatility Modeling. Journal of Econometrics, 157.2 (2010), 306-316.
Kim, S., Shephard, N. & Chib, S. (1998). Stochastic Volatility: Likelihood Inference and Comparison with ARCH Models. The Review of Economic Studies, 65 (3), 361-393.
Mahieu, R., & Schotman, P. (1998). An empirical application of stochastic volatility models. Journal of Applied Econometrics, 13 (4), 333-360.
Nakajima, J. & Omori, Y. (2009). Leverage, heavy-tails and correlated jumps in stochastic volatility models. Computational Statistics & Data Analysis, 53 (6), 2335-2353.
Omori, Y., Chib, S., Shephard, N. & Nakajima, J. (2007). Stochastic volatility with leverage: Fast and efficient likelihood inference. Journal of Econometrics, 140 (2), 425-449.
Shephard, N. & Kim, S. (1994). Bayesian Analysis of Stochastic Volatility Models: Comment. Journal of Business and Economic Statistics, 12.4 (1994): 406-410.
Sironi, A. & Resti, A. (2007). Risk management and shareholders' value in banking: from risk measurement models to capital allocation policies, Vol. 417. John Wiley & Sons, England.
Taylor, S. (1982). Financial returns modeled by the product of two stochastic processes-a study of daily sugar prices. North Holland, Amesterdam.
 Virbickaite, A., Lopez, H., Ausin, M. & Galeano, P. (2014). Particle Learning for Bayesian Non-Parametric Markov Switching Stochastic Volatility Model. UC3M Working papers. 14-19.