Stochastic Volatility Estimation of Stock Prices using the Ensemble Kalman Filter
Abstract
Volatility plays important role in options trading. In their seminal paper published in 1973, Black and Scholes assume that the stock price volatility, which is the underlying security volatility of a call option, is constant. But thereafter, researchers found that the return volatility was not constant but conditional to the information set available at the computation time. In this research, we improve a methodology to estimate volatility and interest rate using Ensemble Kalman Filter (EnKF). The price of call and put option used in the observation and the forecasting step of the EnKF algorithm computed using the solution of Black-Scholes PDE. The state-space used in this method is the augmented state space, which consists of static variables: volatility and interest rate, and dynamic variables: call and put option price. The numerical experiment shows that the EnKF algorithm is able to estimate accurately the estimated volatility and interest rates with an RMSE value of 0.0506.
Keywords: stochastic volatility; call option; put option; Ensemble Kalman Filter.
Abstrak
Volatilitas adalah faktor penting dalam perdagangan suatu opsi. Dalam makalahnya yang dipublikasikan tahun 1973, Black dan Scholes mengasumsikan bahwa volatilitas harga saham, yang merupakan volatilitas sekuritas yang mendasari opsi beli, adalah konstan. Akan tetapi, para peneliti menemukan bahwa volatilitas pengembalian tidaklah konstan melainkan tergantung pada kumpulan informasi yang dapat digunakan pada saat perhitungan. Pada penelitian ini dikembangkan metodologi untuk mengestimasi volatilitas dan suku bunga menggunakan metode Ensembel Kalman Filter (EnKF). Harga opsi beli dan opsi jual yang digunakan pada observasi dan pada tahap prakiraan pada algoritma EnKF dihitung menggunakan solusi persamaan Black-Scholes. Ruang keadaan yang digunakan adalah ruang keadaan yang diperluas yang terdiri dari variabel statis yaitu volatilitas dan suku bunga, dan variabel dinamis yaitu harga opsi beli dan harga opsi jual. Eksperimen numerik menunjukkan bahwa algoritma ENKF dapat secara akurat mengestimasi volatiltas dan suku bunga dengan RMSE 0.0506.
Kata kunci: volatilitas stokastik; opsi beli; opsi jual; Ensembel Kalman Filter.Keywords
References
D. J. Higham, An Introduction to Financial Option Valuation, United Kingdom: Cambridge University Press, 2004.
F. Black and M. Scholes, "The Pricing of Options and Corporate Liabilities," The Journal of Political Economy, vol. 81, no. 3, pp. 637-654, 1973.
F. E. Racicot and R. Theoret, "Forecasting Stochastic Volatility using the Kalman Filter: An Application to Canadian Interest Rates and Price-Earnings Ratio, AESTIMATIO," The IEB International Journal of Finance, vol. 1, pp. 28-45, 2010.
A. E. Ahmed and S. Z. Suliman, "Modelling Stock Market Volatility Using GARCH Models Evidence From Sudan," International Journal of Business and Social Science, vol. 2, no. 23, pp. 114-128, 2011.
R. J. Elliot, T. K. Siu and E. S. Fung, "Filtering a Nonlinear Stochastic Volatility Model," Nonlinear Dyn, vol. 67, pp. 1295-1313, 2012.
I. Burtnyak and A. Malytska, "CEV Model with Stochastic Volatility," Journal of Vasyl Stefanyk Precarpathian National University, vol. 6, no. 3-4, pp. 22-28, 2019.
J.-M. Kim, C. Jun and J. Lee, "Forecasting the Volatility of the Cryptocurrency Market by GARCH and Stochastic Volatility," Mathematics, vol. 9, no. 1614, https://doi.org/10.3390/math9141614, 2021.
K. Nguyen, T.-N. Nguyen and M.-N. Tran, "A dynamic leverage stochastic volatility model," Applied Economics Letters, vol. DOI: 10.1080/13504851.2021.1983127,. https://doi.org/10.1080/13504851.2021.1983127, 2021.
M. Alghalith, C. Floros and K. Gkillas, "Estimating Stochastic Volatility under the Assumption of Stochastic Volatility of Volatility," Risks, vol. 8, no. 35, doi:10.3390/risks8020035 , 2020.
B. E. Awashie, Pricing Financial Options Using Ensemble Kalman Filter, Ghana: Master Thesis of Kwame Nkrumah University of Science and Technology, 2012.
DOI: 10.15408/inprime.v3i2.20256
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