A warrant is a financial agreement that gives the right but not the responsibility, to buy or sell a security at a specific price prior to expiration. Many researchers inadvertently utilize call option pricing models to price equity warrants, such as the Black Scholes model which had been found to hold many shortcomings. This paper investigates the pricing of equity warrants under a hybrid model of Heston stochastic volatility together with stochastic interest rates from Cox-Ingersoll-Ross model. This work contributes to exploration of the combined effects of stochastic volatility and stochastic interest rates on pricing equity warrants which fills the gap in the current literature. Analytical pricing formulas for hybrid equity warrants are firstly derived using partial differential equation approaches. Further, to implement the pricing formula to realistic contexts, a calibration procedure is performed using local optimization method to estimate all parameters involved. We then conducted an empirical application of our pricing formula, the Black Scholes model, and the Noreen Wolfson model against the real market data. The comparison between these models is presented along with the investigation of the models' accuracy using statistical error measurements. The outcomes revealed that our proposed model gives the best performance which highlights the crucial elements of both stochastic volatility and stochastic interest rates in valuation of equity warrants. We also examine the warrants' moneyness and found that 96.875% of the warrants are in-the-money which gives positive returns to investors. Thus, it is beneficial for warrant holders concerned in purchasing warrants to elect the best warrant with the most profitable and more benefits at a future date.
Citation: Teh Raihana Nazirah Roslan, Sharmila Karim, Siti Zulaiha Ibrahim, Ali Fareed Jameel, Zainor Ridzuan Yahya. Stochastic pricing formulation for hybrid equity warrants[J]. AIMS Mathematics, 2022, 7(1): 398-424. doi: 10.3934/math.2022027
A warrant is a financial agreement that gives the right but not the responsibility, to buy or sell a security at a specific price prior to expiration. Many researchers inadvertently utilize call option pricing models to price equity warrants, such as the Black Scholes model which had been found to hold many shortcomings. This paper investigates the pricing of equity warrants under a hybrid model of Heston stochastic volatility together with stochastic interest rates from Cox-Ingersoll-Ross model. This work contributes to exploration of the combined effects of stochastic volatility and stochastic interest rates on pricing equity warrants which fills the gap in the current literature. Analytical pricing formulas for hybrid equity warrants are firstly derived using partial differential equation approaches. Further, to implement the pricing formula to realistic contexts, a calibration procedure is performed using local optimization method to estimate all parameters involved. We then conducted an empirical application of our pricing formula, the Black Scholes model, and the Noreen Wolfson model against the real market data. The comparison between these models is presented along with the investigation of the models' accuracy using statistical error measurements. The outcomes revealed that our proposed model gives the best performance which highlights the crucial elements of both stochastic volatility and stochastic interest rates in valuation of equity warrants. We also examine the warrants' moneyness and found that 96.875% of the warrants are in-the-money which gives positive returns to investors. Thus, it is beneficial for warrant holders concerned in purchasing warrants to elect the best warrant with the most profitable and more benefits at a future date.
[1] | N. I. I. I. Gunawan, S. N. I. Ibrahim, N. A. Rahim, A review on Black-Scholes model in pricing warrants in Bursa Malaysia, In: AIP Conference Proceedings, 1795 (2017), 020013. doi: 10.1063/1.4972157. |
[2] | M. D. Sae-ue, Derivative warrant market and implied volatility, Chulalongkorn University, 2015. |
[3] | W. Xiao, W. Zhang, X. Zhang, X. Chen, The valuation of equity warrants under the fractional Vasicek process of the short-term interest rate, Phys. A, 394 (2014), 320-337. doi: 10.1016/j.physa.2013.09.033. doi: 10.1016/j.physa.2013.09.033 |
[4] | M. R. P. Sakti, A. Qoyum, Testing the warrants mispricing and their determinants: the panel data models, Glob. Rev. Islamic Econ. Bus., 5 (2017), 118-129. doi: 10.14421/grieb.2017.052-05. doi: 10.14421/grieb.2017.052-05 |
[5] | R. Haron, Derivatives, pricing efficiency and gharar: evidence on embedded options in Malaysia, J. Islamic Financ., 3 (2014), 039-048. |
[6] | W. Abbasi, Pricing warrants models: An empirical study of the Indonesian market, Res. J. Econ. Bus. ICT, 10 (2015), 1. |
[7] | K. A. A. Aziz, M. F. I. M. Idris, R. Saian, W. S. W. Daud, Adaptation of warrant price with Black Scholes model and historical volatility, In: AIP Proceedings of Mathematics, 1660 (2015), 090042. doi: 10.1063/1.4915886. |
[8] | D. B. V. Arulanandam, K. W. Sin, M. A. Muita, Relevance of Black Scholes model on Malaysia KLCI options: An empirical study, Internat. J. Financ. Res. Rev., 5 (2017). 1-33. |
[9] | W. Xiao, X. Zhang, Pricing equity warrants with a promised lowest price in Merton's jump-diffusion model, Phys. A, 458 (2016), 219-238. doi: 10.1016/j.physa.2016.03.100. doi: 10.1016/j.physa.2016.03.100 |
[10] | D. Galai, M. I. Schneller, Pricing of warrants and the value of the firm, J. Financ., 33 (1978), 1333-1342. doi: 10.2307/2327269. doi: 10.2307/2327269 |
[11] | G. U. Schulz, S. Trautmann, Robustness of option-like warrant valuation, J. Bank. Financ., 18 (1994), 841-859. doi: 10.1016/0378-4266(94)00030-1. doi: 10.1016/0378-4266(94)00030-1 |
[12] | J. C. Handley, On the valuation of warrants, J. Fut. Mkts., 22 (2002), 765-782. doi; 10.1002/fut.10032. |
[13] | K. G. Lim, E. Terry, The valuation of multiple stock warrants, J. Fut. Mkts., 23 (2003), 517-534. doi: 10.1002/fut.10079. |
[14] | A. D. Ukhov, Warrant pricing using observable variables, J. Financ. Res., 27 (2004), 329-339. doi: 10.1111/j.1475-6803.2004.00100.x. doi: 10.1111/j.1475-6803.2004.00100.x |
[15] | I. Abínzano, J. F. Navas, Pricing levered warrants with dilution using observable variables, Quant. Financ., 13 (2013), 1199-1209. doi: 10.1080/14697688.2013.771280. doi: 10.1080/14697688.2013.771280 |
[16] | A. Bhat, K. Arekar, Empirical performance of Black-Scholes and GARCH option pricing models during turbulent times: The Indian evidence, Int. J. Econ. Financ., 8 (2016), 123-136. doi: 10.5539/ijef.v8n3p123. doi: 10.5539/ijef.v8n3p123 |
[17] | M. Tian, X. Yang, S. Kar, Equity warrants pricing problem of mean-reverting model in uncertain environment, Phys. A, 531 (2019), 121593. doi: 10.1016/j.physa.2019.121593. doi: 10.1016/j.physa.2019.121593 |
[18] | F. Shokrollahi, Valuation of equity warrants for uncertain financial market, 2017, arXiv: 1711.08356. |
[19] | B. Liu, Some research problems in uncertainty theory, J. Uncertain Syst., 3 (2009), 3-10. |
[20] | X. N. Su, W. Wang, W. S. Wang, Pricing warrant bonds with credit risk under a jump diffusion process, Discrete Dyn. Nat. Soc., 2018 (2018), 4601395. doi: 10.1155/2018/4601395. doi: 10.1155/2018/4601395 |
[21] | M. Zili, On the mixed fractional Brownian motion, Int. J. Stoc. Anal., 2006 (2006), 1-9. doi: 10.1155/JAMSA/2006/32435. doi: 10.1155/JAMSA/2006/32435 |
[22] | W. G. Zhang, W. L. Xiao, C. X. He, Equity warrants pricing model under Fractional Brownian motion and an empirical study, Expert Syst. Appl., 36 (2009), 3056-3065. doi: 10.1016/j.eswa.2008.01.056. doi: 10.1016/j.eswa.2008.01.056 |
[23] | J. Hull, Option, futures and other derivatives, 7 Eds., New Jersey: Pearson Education, 2009. |
[24] | N. Noreen, M. Wolfson, Equilibrium warrant pricing models and accounting for executive stock options, J. Account. Res., 19 (1981), 384-398. doi: 10.2307/2490872. doi: 10.2307/2490872 |
[25] | X. J. He, S. P. Zhu, A closed-form pricing formula for European options under the Heston model with stochastic interest rate, J. Comput. Appl. Math., 335 (2018), 323-333. doi: 10.1016/j.cam.2017.12.011. doi: 10.1016/j.cam.2017.12.011 |
[26] | J. Hull, A. White, The pricing of options on assets with stochastic volatilities, J. Financ., 42 (1987), 281-300. doi: 10.1111/j.1540-6261.1987.tb02568.x. doi: 10.1111/j.1540-6261.1987.tb02568.x |
[27] | R. C. Merton, Theory of rational option pricing, Bell J. Econ. Manage. Sci., 4 (1973), 141-183. doi: 10.2307/3003143. doi: 10.2307/3003143 |
[28] | M. Abudy, Y. Izhakian, Pricing stock options with stochastic interest rate, Int. J. Portfolio Anal. Manage., 1 (2013), 250-277. doi: 10.1504/IJPAM.2013.054408. doi: 10.1504/IJPAM.2013.054408 |
[29] | X. J. He, S. P. Zhu, A closed-form pricing formula for European options under the Heston model with stochastic interest rate, J. Comput. Appl. Math., 335 (2018), 323-333. doi: 10.1016/j.cam.2017.12.011. doi: 10.1016/j.cam.2017.12.011 |
[30] | T. R. N. Roslan, A. F. Jameel, S. Z. Ibrahim, Modeling the price of hybrid equity warrants under stochastic volatility and interest rate, COMPUSOFT: Int. J. Adv. Comput. Technol., 9 (2020), 3586-3589. |
[31] | L. A. Grzelak, C. W. Oosterlee, On the Heston model with stochastic interest rates, SIAM J. Financ. Math., 2 (2011), 255-286. doi: 10.1137/090756119. doi: 10.1137/090756119 |
[32] | Y. Shen, T. K. Siu, Pricing variance swaps under a stochastic interest rate and volatility model with regime-switching, Oper. Res. Lett., 41 (2013), 180-187. doi: 10.1016/j.orl.2012.12.008. doi: 10.1016/j.orl.2012.12.008 |
[33] | A. Gnoatto, M. Grasselli, An analytic multi-currency model with stochastic volatility and stochastic interest rates, 2013, arXiv: 1302.7246. |
[34] | T. R. N. Roslan, S. Z. Ibrahim, S. Karim, Hybrid equity warrants pricing formulation under stochastic dynamics, Int. Scholarly Sci. Res. Innov., 14 (2020), 133-136. |
[35] | M. C. Recchioni, Y. Sun, G. Tedeschi, Can negative interest rates really affect option pricing? empirical evidence from an explicitly solvable stochastic volatility model, Quant. Financ., 17 (2017), 1257-1275. doi: 10.1080/14697688.2016.1272763. doi: 10.1080/14697688.2016.1272763 |
[36] | Z. Guo, Option pricing under the Heston model where the interest rate follows the Vasicek model, Commun. Stat. Theor. M., 50 (2021), 2930-2937. doi: 10.1080/03610926.2019.1678643. doi: 10.1080/03610926.2019.1678643 |
[37] | G. Orlando, R. M. Mininni, M. Bufalo, Interest rates calibration with a CIR model, J. Risk Financ., 20 (2019), 370-387. |
[38] | G. Orlando, R. M. Mininni, M. Bufalo, Forecasting interest rates through Vasicek and CIR models: A partitioning approach, J. Forecasting, 39 (2020), 569-579. doi: 10.1002/for.2642. doi: 10.1002/for.2642 |
[39] | F. Black, M. Scholes, The pricing of options and corporate liabilities, J. Polit. Econ., 81 (1973), 637-654. doi: 10.1142/9789814759588_0001. doi: 10.1142/9789814759588_0001 |
[40] | S. L. Heston, A closed-form solution for options with stochastic volatility with applications to bond and currency options, Rev. Financ. Stud., 6 (1993), 327-343. |
[41] | J. Cox, J. E. Ingersoll, S. A. A. Ross, Theory of the term structure of interest, Econometrica, 53 (1985), 129-164. |
[42] | G. Deelstra, Long-term returns in stochastic interest rate models: Applications, Astin Bull., 30 (2000), 123-140. doi: 10.2143/AST.30.1.504629. doi: 10.2143/AST.30.1.504629 |
[43] | G. Deelstra, F. Delbaen, Long-term returns in stochastic interest rate models, Insur. Math. Econ., 17 (1995), 163-169. doi: 10.1016/0167-6687(95)00018-N. doi: 10.1016/0167-6687(95)00018-N |
[44] | P. H. Dybvig, J. E. Ingersoll Jr, S. A. Ross, Long forward and zero-coupon rates can never fall, J. Bus., 69 (1996), 1-25. |
[45] | J. Cao, G. Lian, T. R. N. Roslan, Pricing variance swaps under stochastic volatility and stochastic interest rate, Appl. Math. Comput., 277 (2016), 72-81. doi: 10.1016/j.amc.2015.12.027. doi: 10.1016/j.amc.2015.12.027 |
[46] | J. Cao, T. R. N. Roslan, W. Zhang, The valuation of variance swaps under stochastic volatility, stochastic interest rate and full correlation structure, J. Korean Math. Soc., 57 (2020), 1167-1186. doi: 10.4134/JKMS.J190616. |
[47] | A. Loerx, E. W. Sachs, Model calibration in option pricing, SQUJS, 17 (2012), 84-102. |
[48] | T. Zhang, L. Li, Y. Lin, W. Xue, F. Xie, H. Xu, et al., An automatic and effective parameter optimization method for model tuning, Geosci. Model Dev., 8 (2015), 3579-3591. doi: 10.5194/gmd-8-3579-2015. |
[49] | Y. Cui, S. del Bano Rollin, G. Germano, Full and fast calibration of the Heston stochastic volatility model, Eur. J. Oper. Res., 263 (2017), 625-638. doi: 10.1016/j.ejor.2017.05.018. doi: 10.1016/j.ejor.2017.05.018 |
[50] | H. Gudmundsson, D. Vyncke, A generalized weighted Monte Carlo calibration method for derivative pricing, Mathematics, 9 (2021), 739. doi: 10.3390/math9070739. doi: 10.3390/math9070739 |
[51] | Y. Yen, The effects of structured warrants on firm performance in Malaysia: The role of institutional ownership, 2017. Available from: https://core.ac.uk/download/pdf/231832379.pdf. |