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Page 1: Proceedings of the 17th - uniba.sk · Proceedings of the 17th International Conference on Computational and Mathematical Methods in Science and Engineering, CMMSE 2017 4–8 July,
Page 2: Proceedings of the 17th - uniba.sk · Proceedings of the 17th International Conference on Computational and Mathematical Methods in Science and Engineering, CMMSE 2017 4–8 July,

Proceedings of the 17th

International Conference on Computational and Mathematical

Methods in Science and Engineering

CMMSE-2017

Costa Ballena (Rota), Cádiz, Spain

July 4-8, 2017

Editors

J. Vigo-Aguiar

Associate Editors

J. Medina, M. E. Cornejo, W. Sprößig, T. Sheng, P. Gill, E. Venturino, I. P. Hamilton, J.A. Álvarez-Bermejo, H. Ramos

Page 3: Proceedings of the 17th - uniba.sk · Proceedings of the 17th International Conference on Computational and Mathematical Methods in Science and Engineering, CMMSE 2017 4–8 July,

@CMMSE Preface- Page ii

ISSN: 2312-0177

ISSN-L:2312-0177

ISBN: 978-84-617-8694-7 @Copyright 2017 CMMSE Printed on acid-free paper Cover: A 1754 painting by H.J. Detouche shows Galileo Galilei displaying his telescope to Leonardo Donato and the Venetian Senate.

Page 4: Proceedings of the 17th - uniba.sk · Proceedings of the 17th International Conference on Computational and Mathematical Methods in Science and Engineering, CMMSE 2017 4–8 July,

Contents:

Volume I

Volume I ............................................................................................................................ 1 Linear-time solvers for linear systems with sparse and structured matrices of

interest in applications. J. Abderramán Marrero ...................................................................................................... 2 OpenCL Code Generation for Mobile Devices S. Afonso, A. Acosta and F. Almeid .. ............................................................................... 5 Energetic BEM for soft and hard scattering of 2D damped waves by open arcs A. Aimi, M. Diligenti and C. Guardasoni . ........................................................................... 9 Numerical Pricing of Geometric Asian Options with Barriers A. Aimi and C. Guardasoni . . ........................................................................................... 21 A test for the homogeneity of confusion matrices M.V. Alba-Fernández and F.J. Ariza-López . . ................................................................. 30

Approaching the Rank Aggregation Problem by Local Search-based Metaheuristics J.A. Aledo, J.A. Gámez and D. Molina . ........................................................................... 36

Hermite finite element method for nonlinear Black-Scholes equation governing

European options R.M.P. Almeida, T. D. Chihaluca and J.C.M. Duque. ...................................................... 39 A Fast Implementation of Matrix Trigonometric Functions Sine and Cosine P. Alonso, J. Peinado, J. Ibáñez, J. Sastre and E. Defez . .............................................. 51 Pivoting strategies and almost strictly sign regular matrices P. Alonso, J.M. Peña and M.L Serrano . .......................................................................... 56 Looking for efficiency when avoiding order reduction in nonlinear problems with

Strang splitting I. Alonso-Mallo, B. Cano and N. Reguera . ...................................................................... 64 Fast Iterative Block QR Updating F. J. Alventosa, P. Alonso, A.M. Vidal and G. Piñero . ..................................................... 76 Computer Aided Ship Analysis using Subdivision Schemes S. Amat, M.J. Legaz and J. Ruiz .................................................................................... 80

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A variational approach for chemical kinetics: A case study S. Amat, M.J. Legaz and J. Ruiz . ................................................................................. 87 Approximation of polynomial Hamiltonian systems using an alternative variational

technique S. Amat, M.J. Legaz and J. Ruiz . ................................................................................ 94 Stability analysis of a parametric family of seventh-order iterative methods for

solving nonlinear problems A. R. Amiri, A. Cordero, M.T. Darvishi and J.R. Torregrosa . ....................................... 103 Square cylinder with passive flow control B. AN, , J.M .Bergada and A. Mushyam . .................................................................... 114 Nondominated solutions in a fully fuzzy linear programming problem M. Arana-Jiménez ......................................................................................................... 123 Numerical methods for nonlinear option pricing models with variable transaction

costs I. Arregui, D. Sevcovic and C. Vázquez . ...................................................................... 131 A Fast and Stable Square Root Free Unitary QR Algorithm J.L Aurentz, T. Mach, R. Vandebril and D.S. Watkins ................................................... 140

A stochastic mathematical model of pre-diagnostic glioma growth based on blood

glucose levels L.E. Ayala, A. Gallegos, J.E. Macías-Díaz, M.L. Miranda-Beltrán and H. Vargas-Rodríguez ...................................................................................................................... 144 DRBEM Solutions of the Direct and Inverse Formulations of Cauchy Problem for

the Magnetohydrodynamic Duct Flow C. Aydin and M. Tezer-Sezgin . ..................................................................................... 154 Fluidic actuator performance variation via internal dimensions modifications M. Baghaei, J.M. Bergada, and D. Del Campo . ............................................................ 166 Analysis of OpenACC Performance Using Different Block Geometries D. Barba, A. Gonzalez-Escribano and D.R Llanos. ........................................................ 177 Some statistical approaches to deal with change and confusion matrices obtained

from spatial data I. Barranco-Chamorro . .................................................................................................. 186 Hermite interpolation by many-knot cubic splines: error analysis D. Barrera . ................................................................................................................... 190 Non uniform quasi-interpolation for solving nonlinear Fredholm integral equations

of the second kind D. Barrera, F. El Mokhtari and D. Sbibih . ................................................................... 196 A spline quasi-interpolation based method to obtain the reset voltage in Resistive

RAMs in the Charge-Flux domain D. Barrera, M. J. Ibáñez, F. Jiménez-Molinos, A. M. Roldán and J. B. Roldán. ............. 203 Bigeometric Complex Calculus A.E Bashirov and S. Norozpour .!. ................................................................................. 211 Probabilistic Evolution Theoretical Formulation of Anharmonic Symmetric

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Proceedings of the 17th International Conferenceon Computational and Mathematical Methodsin Science and Engineering, CMMSE 20174–8 July, 2017.

Numerical methods for nonlinear option pricing models

with variable transaction costs

Inigo Arregui1, Daniel Sevcovic2 and Carlos Vazquez1

1 Dept. of Mathematics, University of A Coruna, Spain

2 Dept. of Applied Mathematics and Statistics, Comenius University, Slovakia

emails: [email protected], [email protected], [email protected]

Abstract

The classical Black-Scholes equation for options pricing exhibits several limitationswhen applied to real markets in certain conditions. In many settings, the considera-tion of a constant volatility is no more realistic. In the present paper, we consider thecase where the volatility is assumed to depend on the product of the asset price andthe second derivative of the option with respect to the asset price (an option Greekwhich is known as Gamma). This hypothesis has been made in models that incorporatetransaction costs, market feedback effects related to stocks trading strategies or illiquidmarkets, risks related to unprotected portfolios, etc. In these settings, the correspond-ing nonlinear Black-Scholes equation can be transformed into a quasilinear equation(Gamma equation) in a new unknown variable related to the Gamma of the option.

Once this semilinear Gamma equation has been obtained, we propose a dualitymethod, combined with a characteristics scheme and finite elements methods. Theduality method is applied to the maximal monotone operator that governs the nonlinearterm in the Gamma equation. By a suitable numerical integration technique the value ofthe European option can be recovered. Finally, we present some examples of Europeanoptions to show the good performance of the new numerical global strategy.

Key words: option pricing, option gamma, nonlinear Black–Scholes, duality meth-ods, finite elements

1 Introduction

The classical linear Black–Scholes presented in 1973 establishes that the price V of an optioncan be obtained as the solution of the parabolic equation:

∂tV +σ2

2S2 ∂2

SV + rS∂SV − rV = 0 , (1)

c©CMMSE ISBN: 978-84-617-8694-7Page 131 of 2288

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Numerical solution of a nonlinear pricing model

where r > 0 denotes the risk–free interest rate and σ is the (constant) volatility of theunderlying asset, the price of which is assumed to be a stochastic process that follows thestochastic differential equation

dSt = µSt dt+ σSt dWt ,

the constant µ being the drift and the process Wt a geometric Brownian motion. Note thatthe option price, Vt, is a process that is obtained from the solution V of (1), by the expressionVt = V (t, St). Equation (1) has been derived under several restrictive assumptions.

However, from the analysis of market data, the need of more realistic models arises.For example, in several setting, different models assume nonconstant volatility expressionsthat depend on the gamma of the option in the form:

σ = σ(S ∂2SV ) ,

so that the following nonlinear Black–Scholes equation is posed:

∂tV +1

2σ(S∂2

SV )2S2 ∂2SV + rS∂SV − rV = 0. (2)

For example, this kind of dependency arises in option pricing models that take into accountnon-trivial variable transaction costs related to assets buying and selling [1, 2, 10], marketfeedback effects due to large traders choosing given stock–trading strategies [6, 7], risk fromvolatile and unprotected portfolios [8], or investor preferences [4], among others.

2 Mathematical model

In this section, we just remind a result by Sevcovic and Zitnanska [11] that establishes theequivalence between the nonlinear Black–Scholes equation (2) and a quasilinear parabolicequation. For this purpose, we introduce the function

β(H) =σ(H)2

2H .

Proposition (Sevcovic–Zitnanska, [11]) Assume the function V = V (S, t) is a solutionto the nonlinear Black–Scholes equation

∂tV + S β(S∂2SV ) + rS∂SV − rV = 0 , S > 0 , t ∈ (0, T ) . (3)

Then the transformed function H = H(x, τ) = S∂2SV (S, t), where x = ln(S/E), τ = T − t,

is a solution to the quasilinear parabolic (Gamma) equation:

∂τH = ∂2xβ(H) + ∂xβ(H) + r∂xH . (4)

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I. Arregui, D. Sevcovic, C. Vazquez

On the other hand, if H is a solution to (4) such that H(−∞, τ) = ∂xH(−∞, τ) = 0 andβ′(0) is finite, then the function

V (S, t) = aS + b exp(−r(T − t)) +

∫ +∞

−∞

(S − E exp(ξ))+H(ξ, T − t) dξ (5)

is a solution to the nonlinear Black–Scholes equation (3) for any a, b ∈ R.

Moreover, if we consider the initial condition

H(x, 0) = δ(x) , (6)

where δ(x) denotes the Dirac delta function with basis point x, then we can recover thepayoffs of the European vanilla options with the choices:

• a = b = 0, for the call option (i.e. V (S, T ) = (S − E)+),

• a = −1, b = E, for the put option (i.e. V (S, T ) = (E − S)+),

the constant E being the strike price. As the analytical expression for the solution of (4) isnot available, in next section we propose a set of numerical techniques for its approximation(see e.g. [8, 9, 11] for other numerical strategies).

3 Numerical solution of the quasilinear parabolic equation

In order to solve numerically the nonlinear equation (4) jointly with the initial condition (6),we note the main difficulties: the possibility of advection term dominating diffusion one, thenonlinear diffusion term, the presence of an unbounded domain and the Dirac delta functionin the initial condition. First, as in other problems in which advection can dominate overdiffusion, we propose the characteristics method for the time discretization. Secondly, as thenonlinear term can be related to maximal monotone operators [3], we make use of a dualitymethod based on a result in [5]. In order to deal with the unbounded domain, as usually infinancial problems, we propose a domain truncation in the asset variable by taking S∞ = 4E,which corresponds to x∞ as the upper finite boundary of the computational domain in x.Also we consider x0 as the lower boundary of this domain Ω = (x0, x∞). Concerning tothe Dirac delta function, we approximate it by a Gaussian density. Finally, a finite elementmethod is proposed for the discretization in the spatial-like variable x at each time step.

So, first following [3, 5], we introduce the parameter ω > 0 and a new variable θ givenin terms of the function βω by:

θ = βω(H) = β(H)− ωH . (7)

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Numerical solution of a nonlinear pricing model

As β(H) = θ + ωH, equation (4) can be equivalently written as:

Hτ − (ω + r)Hx − ωHxx = θx + θxx . (8)

Next, in order to apply the method of characteristics, we introduce the material derivativeof function H:

DH

Dτ= Hτ − (ω + r)Hx , (9)

which represents the derivative associated to the constant scalar velocity field −(ω + r), sothat (8) turns into:

DH

Dτ− ωHxx = θx + θxx . (10)

Note that (10) is still a nonlinear problem, as θ and H are related by (7).

In order to discretize (10) in time by the characteristics (also known as semilagrangian)method, we introduce the time stepsize ∆τ > 0 and mesh points in time τn = n∆τ forn = 0, 1, 2, . . ., so that we consider the following final value problem:

dτ= −(ω + r)χ(τ)

χ(τn+1) = x ,

that provides the characteristics curve (associated to the scalar velocity field) passingthrough the point x at time τn+1. Its analytical solution provides the position at timeτn to be used in the characteristics method:

χn(x) = χ(x, τn+1; τn) = x exp((ω + r)∆τ) .

We can now approximate the material derivative in (10) by a first order upwindedquotient. If we denote Hn(·) = H(·, τn), then (10) is approximated by:

Hn+1 −Hn χn

∆τ− ωHn+1

xx = θn+1x + θn+1

xx . (11)

We will consider homogeneous Dirichlet boundary conditions on ∂Ω, i.e. H(x0) = H(x∞) =0. Thus, the variational formulation of (11) consists in finding Hn+1 ∈ W 1,2

0 (Ω), such that:∫

ΩHn+1ϕ−∆τω

ΩHn+1

xx ϕ =

Ω(Hnχn)ϕ+∆τ

Ωθn+1x ϕ+∆τ

Ωθn+1xx ϕ , ∀ϕ ∈ W 1,2

0 (Ω)

where W 1,20 (Ω) stands for the classical notation of Sobolev spaces. Next, using Green’s

theorem, we get:∫

ΩHn+1ϕ+∆τω

ΩHn+1

x ϕx =

Ω(Hn χn)ϕ+∆τ

Ωθn+1x ϕ−∆τ

Ωθn+1x ϕx

+∆τω

∂ΩHn+1

x ϕ+∆τ

∂Ωθn+1x ϕ .

c©CMMSE ISBN: 978-84-617-8694-7Page 134 of 2288

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I. Arregui, D. Sevcovic, C. Vazquez

Taking into account the homogeneous boundary conditions, the two integrals on ∂Ω vanishand we get:

ΩHn+1ϕ+∆τω

ΩHn+1

x ϕx =

Ω(Hn χn)ϕ+∆τ

Ωθn+1x ϕ−∆τ

Ωθn+1x ϕx , (12)

jointly with the relation:

θn+1 = βω(Hn+1) . (13)

We propose the following fixed point algorithm to solve (12)-(13) at each time instantτn+1. Assume (Hn+1,0, θn+1,0) is given. Then, for k = 0, 1, . . .

• For given (Hn+1,k, θn+1,k), we search Hn+1,k+1 as the solution of the linear problem

ΩHn+1,k+1ϕ+∆τω

ΩHn+1,k+1

x ϕx =

Ω(Hnχn)ϕ+∆τ

Ωθn+1,kx ϕ−∆τ

Ωθn+1,kx ϕx

(14)for all ϕ ∈ W 1,2

0 (Ω).

• We update θn+1,k+1 by solving the nonlinear equation (13). As the exact solution isnot available in most cases, we make use the theory of maximal monotone operatorsas in [5] and propose the updating:

θn+1,k+1 = βωλ (H

n+1,k+1 + λθn+1,k) , (15)

where βωλ denotes the Yosida regularization of function βω with parameter λ:

βωλ (H) = inf

G

(

βω(G) +(G−H)2

)

.

Moreover, for convergence reasons, we choose λ = 1/(2ω).

We note that Yosida regularization is strongly dependent on the function β and requiresthe computation of the inverse of an operator. Therefore, it is not always possible to get itsanalytical expression. This is the reason why we replace (15) by first order Taylor expansion:

θn+1,k+1 = βωλ (H

n+1,k+1 + λθn+1,k)

= βω(Hn+1,k+1 + λθn+1,k − λθn+1,k+1)

= βω(

Hn+1,k+1 + λ(θn+1,k − θn+1,k+1))

= βω(

Hn+1,k+1)

+ (βω)′(

Hn+1,k+1)

λ(θn+1,k − θn+1,k+1)

+ o(

λ2(θn+1,k − θn+1,k+1)2)

, (16)

c©CMMSE ISBN: 978-84-617-8694-7Page 135 of 2288

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Numerical solution of a nonlinear pricing model

which does not require the computation of the Yosida regularization and is accurate enoughif λ is small. From (16), we deduce:

θn+1,k+1[

1 + (βω)′(Hn+1,k+1)λ]

= βω(Hn+1,k+1) + (βω)′(Hn+1,k+1)λθn+1,k

so that:

θn+1,k+1 =βω(Hn+1,k+1) + (βω)′(Hn+1,k+1)λθn+1,k

1 + λ(βω)′(Hn+1,k+1).

Finally, taking into account that βω(H) = β(H)− ωH we obtain:

θn+1,k+1 =β(Hn+1,k+1)− ωHn+1,k+1 +

[

β′(Hn+1,k+1)− ω]

λθn+1,k

1 + λ [β′(Hn+1,k+1)− ω]

=β(Hn+1,k+1) + β′(Hn+1,k+1)λθn+1,k − ω

[

Hn+1,k+1 + λθn+1,k]

1− ωλ+ λβ′(Hn+1,k+1). (17)

The last expression is used instead of (15) to update θn+1. Let us remark that the firstderivative of β is used in (14). In practice, it is approximated by a second order centraldifferences formula. If the function β is not differentiable, it can be replaced by a regularizedfunction β.

For solving (14), we implement a finite element method. Thus, for a fixed naturalnumber M > 0, we consider a uniform mesh of the computational domain Ω = [x0, x∞], thenodes of which are xj = x0+j∆x, j = 0, . . . ,M+1, where ∆x = (x∞−x0)/(M+1) denotesthe constant mesh step. Associated to this uniform mesh a piecewise linear Lagrange finiteelements discretization is considered.

More precisely, we search Hn+1,k+1h ∈ W0,h such that:

ΩHn+1,k+1

h ϕ+∆τω

ΩHn+1,k+1

h,x ϕx =

Ω(Hn

h χn)ϕ+∆τ

Ωθn+1,kx ϕ−∆τ

Ωθn+1,kx ϕx ,

for all ϕ ∈ W0,h, where the space of finite elements is:

W0,h =

vh : Ω → R / vh|[xk,xk+1]∈ P1 for k = 0, 1, . . . ,M, vh = 0 on ∂Ω

,

P1 being the space of polynomials of degree less or equal than one. The coefficients ofthe matrix and right hand side vector defining the linear system associated to the fullydiscretized problem are approximated by adequate quadrature formulae, when necessary.In particular, a five nodes Gaussian formula has been used. Finally, the system of linearequations is solved by a conjugate gradient method.

Once the function H is approximated at each time instant, we can recover the value ofthe derivative by means of (5), where a = b = 0 for a call option and a = −1, b = E for aput option.

c©CMMSE ISBN: 978-84-617-8694-7Page 136 of 2288

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I. Arregui, D. Sevcovic, C. Vazquez

4 Numerical results

In this section we present a numerical result concerning Amster et al model [1, 2], in whichthe nonlinear function β is given by

β(H) =σ2

2(H − Le|H|+ κH2) ,

with σ = 0.95, κ = 0.10 and Le = 0.30. As the function β is not differentiable due to thepresence of the absolute value, we introduce the regularized function βǫ:

βǫ(H) =σ2

2(H − Le fǫ(H) + κH2) .

The function fǫ is a smooth approximation of the absolute value function and its firstderivative is given by:

f ′ǫ(H) =

−1 , if H < −ǫ

s(H) , if − ǫ ≤ H ≤ ǫ

1 , if H > ǫ

s being a cubic spline and ǫ = 10−3.We have considered the case of European call and put options, the payoff of which is

given in terms of the strike price E = 100. Moreover, we have taken the risk-free interestrate r = 0.05 and the maturity T = 4.

For the numerical solution, the time domain has been discretized in 800 steps, thus∆τ = 0.005 and the spatial variable x is in [−4, 1.4], for which we have considered auniform mesh consisting of 1601 nodes. Figure 1 shows the payoff of the call option as wellas the solution at time t = 0 (or τ = 4), while Figure 2 shows analogous results for the putoption.

5 Conclusions

A nonlinear model for derivatives pricing is solved by a numerical strategy including dualitymethods based on maximal monotone operators, characteristics methods for time discretiza-tion and finite elements. The method is independent of the nonlinear function β.

Acknowledgements

First and third authors have been partially supported by Spanish Government (Ministeriode Economıa y Competitividad, project MTM2016-76497-R) and Xunta de Galicia (Gruposde Referencia Competitiva 2014). The second author has been supported by grant VEGA1/0780/15.

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Numerical solution of a nonlinear pricing model

20 40 60 80 100 120 140 160 1800

20

40

60

80

100

120

20 40 60 80 100 120 140 160 1800

20

40

60

80

100

120

Figure 1: Call option. The terminal condition (payoff) and numerical solution

0 50 100 150 2000

20

40

60

80

100

0 50 100 150 2000

20

40

60

80

100

Figure 2: Put option. The terminal condition (payoff) and numerical solution

References

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I. Arregui, D. Sevcovic, C. Vazquez

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