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Properties of a Diversified World Stock Index
Eckhard PlatenSchool of Finance and Economics and School of Mathematical Sciences
University of Technology, Sydney
Platen, E.& Heath, D.: A Benchmark Approach to Quantitative Finance
Springer Finance, 700 pp., 199 illus., Hardcover, ISBN-10 3-540-26212-1 (2006).
Le, T. & Platen. E.: Approximating the growth optimal portfolio with a diversified
world stock index.J. Risk Finance7(5), 559–574 (2006).
Platen, E.& Sidorowicz, R.:Empirical evidence on Student-t log-returns of diversified
world stock indices. University of Technology, Sydney. QFRC Research Paper 194 (2007).
1 23
Springer Finance
A Benchmark Approach to Q
uantitative Finance
1 A Benchmark Approach to
Quantitative Finance
S F
Platen · Heath
Eckhard Platen David Heath
Dieser Farbausdruck/pdf-file kann nur annähernddas endgültige Druckergebnis w
iedergeben !63575
15.5.06 designandproduction GmbH – Bender
Springer Finance
E. Platen · D. HeathThe benchmark approach provides a general framework for financial market
modeling, which extends beyond the standard risk neutral pricing theory.
It allows for a unified treatment of portfolio optimization, derivative pricing,
integrated risk management and insurance risk modeling. The existence of an
equivalent risk neutral pricing measure is not required. Instead, it leads to
pricing formulae with respect to the real world probability measure. This yields
important modeling freedom which turns out to be necessary for the derivation
of realistic, parsimonious market models.
The first part of the book describes the necessary tools from probability theory,
statistics, stochastic calculus and the theory of stochastic differential equations
with jumps. The second part is devoted to financial modeling under the bench-
mark approach. Various quantitative methods for the fair pricing and hedging
of derivatives are explained. The general framework is used to provide an under-
standing of the nature of stochastic volatility.
The book is intended for a wide audience that includes quantitative analysts,
postgraduate students and practitioners in finance, economics and insurance.
It aims to be a self-contained, accessible but mathematically rigorous introduction
to quantitative finance for readers that have a reasonable mathematical or quanti-
tative background. Finally, the book should stimulate interest in the benchmark
approach by describing some of its power and wide applicability.
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ISBN 3-540-26212-1
› springer.com
Benchmark Approach
Pl. & Heath (2006)
• best performing strictly positive portfolio as benchmark
• growth optimal portfolio (GOP)
• benchmark in portfolio optimization
• numeraire in derivative pricing
• approximate GOPs
• Diversification Theorem
Eckhard Platen AMAMEF07, Bedelow 1
• log-return density for diversified stock indices
Markowitz & Usmen (1996a, 1996b):
S&P500 log-returns
Studentt (4.5)
Hurst & Pl. (1997):
regional stock market indices
symmetric generalized hyperbolic distribution
Studentt (3.0)–(4.5)
Eckhard Platen AMAMEF07, Bedelow 2
Fergusson & Pl. (2006):
maximum likelihood ratio test
Studentt (4)
McNeil, Frey & Embrechts (2005):
Studentt type log-returns
Pl. & Sidorowicz (2007):
EWI104s
Studentt (4)
99.9% significance
Eckhard Platen AMAMEF07, Bedelow 3
• benchmark approach
Pl. & Heath (2006)
• growth optimal portfolio (GOP)
Kelly (1956)
• diversified portfolios (DPs)
diversification theorem
Pl. (2005)
equally weighted index (EWI)
EWI104s
Eckhard Platen AMAMEF07, Bedelow 4
Index Construction
• market capitalization weighted indices (MCIs)
• diversity weighted indices (DWIs)
Fernholz (2002)
• equally weighted indices (EWIs)
• world stock indices (WSIs)
Le & Pl. (2006)
Eckhard Platen AMAMEF07, Bedelow 5
• portfolio generating function
given any fractions
πδ,t = (π1δ,t, π
2δ,t, . . . , π
dδ,t)
⊤
forms vector of nonnegative fractions
πδ,t = (π1δ,t, π
2δ,t, . . . , π
dδ,t)
⊤ = A(πδ,t) ∈ [0, 1]d
d∑
j=1
πjδ,t = 1
Eckhard Platen AMAMEF07, Bedelow 6
Market Capitalization Weighted Indices
MCI
πjδMCI ,t
=δ
jtS
jt
∑d
i=1 δitS
it
δjt number of units ofjth constituent
Eckhard Platen AMAMEF07, Bedelow 7
Diversity Weighted Index
DWI
Fernholz (2002)
πjδ,t =
(πjδMCI ,t
)p
∑d
l=1(πlδMCI ,t
)p
p ∈ [0, 1]
p = 0.5
Eckhard Platen AMAMEF07, Bedelow 8
Equally Weighted Index
EWI
πjδEWI,t
=1
d
j ∈ {1, 2, . . . , d}
Eckhard Platen AMAMEF07, Bedelow 9
world stock index
WSI
πjδ,t =
(πjδ,t + µt)
p
∑d
l=1(πlδ,t + µt)p
fractions of GOP
πδ∗,t = Σ−1t (at − rt1)
µt =∣
∣ infjπ
jδ,t
∣
∣+ µ
Eckhard Platen AMAMEF07, Bedelow 10
28/08/76 18/02/82 11/08/87 31/01/93 24/07/98 14/01/04 0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
WSI
EWI
DWI
MCI
Figure 1: Indices constructed from regional stock market indices.
Eckhard Platen AMAMEF07, Bedelow 11
28/08/76 18/02/82 11/08/87 31/01/93 24/07/98 14/01/04 0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
WSI35s
EWI35s
DWI35s
MCI35s
Figure 2: Indices constructed from sector indices based on 35 industries.
Eckhard Platen AMAMEF07, Bedelow 12
28/08/76 18/02/82 11/08/87 31/01/93 24/07/98 14/01/04 0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
EWI104s
WSI104s
DWI104s MCI104s
Figure 3: Indices constructed from sector indices based on 104 industries.
Eckhard Platen AMAMEF07, Bedelow 13
28/08/76 18/02/82 11/08/87 31/01/93 24/07/98 14/01/04 10
1
102
103
104
EWI
EWI104s
Figure 4: The regional EWI and sector EWI104s indices in log-scale.
Eckhard Platen AMAMEF07, Bedelow 14
Log-return Distributions
Barndorff-Nielsen (1978), Hurst & Pl. (1997)McNeil, Frey & Embrechts (2005)
• normal mean-variance mixture distribution
X = m(W ) +√WσZ
Z ∼ N(0, 1)
W ≥ 0 is nonnegative random variable
independent ofZ
• symmetric case =⇒ normal variance-mixture distribution
X =√WσZ
Eckhard Platen AMAMEF07, Bedelow 15
Generalized Hyperbolic Distributions
mixing density
generalized inverse Gaussian
W ∼ GIG(λ, χ, ψ)
X ∼ GH(λ, χ, ψ, µ, σ, γ)
fX(x) =ψλ(ψ + γβ)
12−λ(
√χψ)−λ
√2πσKλ(
√χψ)
Kλ−12
(
√
(χ+Q)(ψ + γβ))
(
√
(χ+Q)(ψ + γβ))
12−λ
eξβ
ξ = x− µ, β = γσ−2, Q = (x− µ)2σ−2
Kλ(·) modified Bessel function of the third kind
Eckhard Platen AMAMEF07, Bedelow 16
• symmetric generalized hyperbolic density
fX(x) =1
δσKλ(α)
√
α
2π
(
1+x2
(δσ)2
)12 (λ−
12 )
Kλ−12
(
α
√
1 +x2
(δσ)2
)
λ ∈ ℜ,α, δ ≥ 0, α 6= 0 if λ ≥ 0, δ 6= 0 if λ ≤ 0
α = αδ
unique scale parameter
c2 =
(δσ)2
−2(λ+1)if α = 0 for λ < 0 andα = 0,
2λσ2
α2 , if δ = 0 for λ > 0 andα = 0,(δσ)2Kλ+1(α)
αKλ(α)otherwise
Eckhard Platen AMAMEF07, Bedelow 17
Special Cases of the SGH Distribution
• Variance Gamma:α = 0 and λ > 0
Madan & Seneta (1990)
• Studentt: α = 0 andλ < 0
Praetz (1972)
• Hyperbolic: λ = 1
Eberlein & Keller (1995)
• Normal Inverse Gaussian:λ = −0.5
Barndorff-Nielsen (1995)
Eckhard Platen AMAMEF07, Bedelow 18
Variance Gamma Density
α = 0, α =√
2λ, δ = 0
gamma distribution mixing
fX(x) =
√λ
√πσ2λ−1Γ(λ)
(√2λ|x|σ
)λ−12
Kλ−12
(√2λ|x|σ
)
Madan & Seneta (1990)
Eckhard Platen AMAMEF07, Bedelow 19
Student t Density
Praetz (1972), Blattberg & Gonedes (1974)
inverse gamma distribution mixing
degrees of freedomν = −2λ ≥ 2
fX(x) =2
1−ν
2
Γ(
ν2
)√πνσ
(
1 +Q
ν
)−ν+12 K ν+1
2
(
√
(ν +Q)γβ)
(
√
(ν +Q)γβ)−
ν+12
eξβ
Eckhard Platen AMAMEF07, Bedelow 20
Likelihood Ratio Test
• likelihood ratio
Λ =L∗
model
L∗nesting model
L∗model maximized likelihood function
• test statistic
Ln = −2 ln(Λ)
Eckhard Platen AMAMEF07, Bedelow 21
P (Ln < χ21−α,1) ≈ Fχ2(1)(χ
21−α,1) = 1 − α
Ln < χ20.01,1 ≈ 0.000157
Ln < χ20.001,1 ≈ 0.000002
not rejected at the99.9% level
Eckhard Platen AMAMEF07, Bedelow 22
Fitted Log-return Distributions
daily log-returns 1973 – 2006
EWI104s
denominated in 27 currencies
> 200.000 observations
Eckhard Platen AMAMEF07, Bedelow 23
−10 −5 0 5 10
10−4
10−3
10−2
10−1
Figure 5: Log-histogram of the EWI104s log-returns and Student t density
with four degrees of freedom.Eckhard Platen AMAMEF07, Bedelow 24
0
0.5
1
1.5
2
−5−4
−3−2.15
−10
1 2
34
5
−2.94
−2.92
−2.9
−2.88
−2.86
−2.84
αλ
Estimated λ
Estimated LLF
× 105
Figure 6: Log-likelihood function based on the EWI104s.
Eckhard Platen AMAMEF07, Bedelow 25
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1MCI
α
λ
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1DWI
α
λ
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1EWI
α
λ
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1WSI
α
λ
Figure 7:(α, λ)-plot for log-returns of indices in different currencies con-
structed from regional stock market indices as constituents.Eckhard Platen AMAMEF07, Bedelow 26
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1MCI35s
α
λ
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1DWI35s
α
λ
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1EWI35s
α
λ
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1WSI35s
α
λ
Figure 8:(α, λ)-plot for log-returns of indices in different currencies con-
structed from 35 sector indices as constituents.Eckhard Platen AMAMEF07, Bedelow 27
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1MCI104s
α
λ
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1DWI104s
α
λ
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1EWI104s
α
λ
0 0.2 0.4 0.6−3
−2.5
−2
−1.5
−1WSI104s
α
λ
Figure 9:(α, λ)-plot for log-returns of indices in different currencies con-
structed from 104 sector indices as constituents.Eckhard Platen AMAMEF07, Bedelow 28
SGH Studentt NIG Hyperbolic VG
σ 0.9807068 0.7191163 0.9697258 0.9584118 0.9593693
α 0.0000000 0.9694605 0.7171357
λ -2.1629649 1.4912414
ν 4.3259646
ln(L∗) -285796.3865295 -285796.3865297 -286448.9371892 -287152.0787956 -287499.8259143
Ln 0.0000004 1305.1013194 2711.3845322 3406.8787696
Table 1: Results for log-returns of the EWI104s
Eckhard Platen AMAMEF07, Bedelow 29
Country Student-t NIG Hyperbolic VG ν
Australia 0.000000 76.770817 150.202282 181.632971 4.281222
Austria 0.000000 39.289103 77.505683 102.979330 4.725907
Belgium 0.000000 31.581622 60.867570 83.648470 4.989912
Brazil 2.617693 5.687078 63.800349 60.078395 2.713036
Canada 0.000000 47.506215 79.917741 104.297607 5.316154
Denmark 0.000000 41.509921 87.199686 114.853658 4.512101
Finland 0.000000 28.852844 68.677271 88.553080 4.305638
France 0.000000 26.303544 57.639325 80.567283 4.722787
Germany 0.000000 27.290205 52.667918 71.120798 5.005856
Greece 0.000000 60.432172 104.789463 125.601499 4.674626
Hong.Kong 0.000000 42.066531 100.834255 122.965326 3.930473
India 0.000000 74.773701 163.594078 198.002956 3.998713
Ireland 0.000000 77.727856 136.505582 170.013644 4.761519
Italy 0.000000 25.196598 55.185625 75.481897 4.668983
Japan 0.000000 37.630363 77.163656 102.967380 4.649745
Korea.S. 0.000000 120.904983 304.829431 329.854620 3.289204
Eckhard Platen AMAMEF07, Bedelow 30
Malaysia 0.000000 79.714054 186.013963 221.061290 3.785195
Netherlands 0.000000 26.832761 51.625813 71.541627 5.084056
Norway 0.000000 42.243851 89.012090 115.059003 4.472349
Portugal 0.000000 61.177624 137.681039 165.689683 3.984860
Singapore 0.000000 36.379685 77.600590 98.124375 4.251472
Spain 0.000000 56.694545 109.533768 138.259224 4.517153
Sweden 0.000000 77.618384 143.420049 178.983373 4.546640
Taiwan 0.000000 41.162560 96.283628 115.186585 3.914719
Thailand 0.000000 78.250621 254.590254 267.508143 3.032038
UK 0.000000 26.693076 55.937248 80.678494 4.952843
USA 0.000000 40.678242 79.617362 100.901197 4.636661
Table 2:Ln test statistic of the EWI104s for different currency denominations
Eckhard Platen AMAMEF07, Bedelow 31
Stochastic Volatility Model
mixing density for returns is inverse gamma
• squared volatility
dσ2t =
1
4γ2(ν + 2 − 4 ξ)σ
4(ξ−1)t
(
σ2 − σ2t
)
dt+ γ σ2ξ dWt
stationary density is inverse gamma
Heath, Hurst & Pl. (2001)
d
dt
[
ln(σ2)]
t= γ2 σ
2(ξ−1)t ≈ γ2 =⇒ ξ = 1
Eckhard Platen AMAMEF07, Bedelow 32
0 2000 4000 6000 8000
−0.10
−0.05
0.00
0.05
Figure 10: Returns of industry index.
Eckhard Platen AMAMEF07, Bedelow 33
DF= 4.4679
−4 −2 0 2 4
0.00.1
0.20.3
0.4
Figure 11: Histogram of returns.
Eckhard Platen AMAMEF07, Bedelow 34
0 2000 4000 6000 8000
0.000
00.0
005
0.001
00.0
015
0.002
0
Figure 12: Squared volatility.
Eckhard Platen AMAMEF07, Bedelow 35
DF= 4.4554
0 50000 100000 150000 200000
0.0 e+
001.0
e−05
2.0 e−
053.0
e−05
Figure 13: Histogram of inverse squared volatility.
Eckhard Platen AMAMEF07, Bedelow 36
0 2000 4000 6000 8000
050
100
150
200
250
300
350
Figure 14: Quadratic variation of log-squared volatility.
Eckhard Platen AMAMEF07, Bedelow 37
Financial Market Model
• Wiener processesBk = {Bkt , t ∈ R+} for k ∈ {1, 2, . . . ,m}
• compensated normalized jump martingales
dqkt = (hk
t )−
12 (dpk
t − hkt dt)
• trading uncertainties
W = {Wt = (W 1t , . . . ,W
mt ,W
m+1t , . . . ,W d
t )⊤, t ∈ R+}
W 1t = B1
t , . . . ,Wmt = Bm
t
Wm+1t = q
m+1t , . . . ,W d
t = qdt
Eckhard Platen AMAMEF07, Bedelow 38
• primary security accounts
savings account
S0t = exp
{∫ t
0
rsds
}
< ∞
jth risky asset
dSjt = S
jt−
(
ajtdt+
d∑
k=1
bj,kt dW k
t
)
volatility matrix invertible
assume
bj,kt ≥ −
√
hkt
Eckhard Platen AMAMEF07, Bedelow 39
• market price of risk
θt = (θ1t , . . . , θ
dt )⊤ = b
−1t (at − rt 1)
assume
θkt <
√
hkt
Eckhard Platen AMAMEF07, Bedelow 40
• portfolio
Sδt =
d∑
j=0
δjt S
jt
• fraction
πjδ,t = δ
jt
Sjt
Sδt
dSδt = Sδ
t−
(
rt dt+ π⊤
δ,tbt (θt dt+ dWt))
assume
πjδ,t ≥ 0
Eckhard Platen AMAMEF07, Bedelow 41
Growth Optimal Portfolio
dSδ∗
t = Sδ∗
t−
(
rt dt+
m∑
k=1
θkt (θk
t dt+ dW kt )
+
d∑
k=m+1
θkt
1 − θkt (hk
t )−
12
(
θkt dt+ dW k
t
)
lim supT →∞
1
Tln
(
SδT
Sδ0
)
≤ lim supT →∞
1
Tln
(
Sδ∗
T
Sδ∗
0
)
Eckhard Platen AMAMEF07, Bedelow 42
• sequence of diversified portfolios (DPs)
|πjδ,t| ≤ K2
d12+K1
• assume sequence of markets
regular :
E(
(σk(d)(t))
2)
≤ K
k ∈ {1, 2, . . . , d}
Eckhard Platen AMAMEF07, Bedelow 43
• tracking rate
Rδ(d)(t) =
d∑
k=1
d∑
j=0
πjδ,t σ
j,k
(d)(t)
2
Rδ∗
(d)(t) = 0
• Diversification Theorem
For any DP
limd→∞
Rδ(d)(t)
P= 0
for all t ∈ R+
model independent
Eckhard Platen AMAMEF07, Bedelow 44
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Scand. J. Statist.5, 151–157.
Barndorff-Nielsen, O. (1995). Normal-Inverse Gaussian processes and the modelling ofstock returns. Technical report, University of Aarhus. 300.
Blattberg, R. C. & N. Gonedes (1974). A comparison of the stable and Student distributionsas statistical models for stock prices.J. Business47, 244–280.
Eberlein, E. & U. Keller (1995). Hyperbolic distributions in finance.Bernoulli1, 281–299.
Fergusson, K. & E. Platen (2006). On the distributional characterization of log-returns of aworld stock index.Appl. Math. Finance13(1), 19–38.
Fernholz, E. R. (2002).Stochastic Portfolio Theory, Volume 48 ofAppl. Math.Springer.
Heath, D., S. R. Hurst, & E. Platen (2001). Modelling the stochastic dynamics of volatilityfor equity indices.Asia-Pacific Financial Markets8, 179–195.
Hurst, S. R. & E. Platen (1997). The marginal distributions of returns and volatility. InY. Dodge (Ed.),L1-Statistical Procedures and Related Topics, Volume 31 ofIMS Lec-ture Notes - Monograph Series, pp. 301–314. Institute of Mathematical Statistics Hay-ward, California.
Eckhard Platen AMAMEF07, Bedelow 45
Kelly, J. R. (1956). A new interpretation of information rate.Bell Syst. Techn. J.35, 917–926.
Le, T. & E. Platen (2006). Approximating the growth optimal portfolio with a diversifiedworld stock index.J. Risk Finance7(5), 559–574.
Madan, D. & E. Seneta (1990). The variance gamma (V.G.) modelfor share market returns.J. Business63, 511–524.
Markowitz, H. & N. Usmen (1996a). The likelihood of various stock market return distribu-tions, Part 1: Principles of inference.J. Risk& Uncertainty13(3), 207–219.
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McNeil, A., R. Frey, & P. Embrechts (2005).Quantitative Risk Management. Princeton Uni-versity Press.
Platen, E. (2005). Diversified portfolios with jumps in a benchmark framework.Asia-PacificFinancial Markets11(1), 1–22.
Platen, E. & D. Heath (2006).A Benchmark Approach to Quantitative Finance. SpringerFinance. Springer.
Platen, E. & Sidorowicz (2007). Empirical evidence on Student-t log-returns of diversifiedworld stock indices. Technical report, University of Technology, Sydney. QFRC Re-search Paper 194.
Eckhard Platen AMAMEF07, Bedelow 46
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Eckhard Platen AMAMEF07, Bedelow 47