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Chapter 15
Stochastic Volatility Models with Jumps
In Chap. 9, we considered pure diffusion stochastic volatility models. In particular,
we assumed that the vector process
Z
=
(X, Y
1
,...,Y
n
v
)
of the log-price process
X
=
1 additional processes which describe the volatility
σ
t
=
ξ(Y
t
,...,Y
n
t
)
satisfies the SDE d
Z
t
=
ln
(S)
and the
n
v
≥
+
b(Z
t
)
d
t
Σ(Z
t
)
d
W
t
. We extend these
models by adding jumps to it.
15.1 Market Models
Let
(Ω,
)
be a filtered complete probability space satisfying the usual hy-
potheses (see Sect. 1.2). Let
(W
t
)
t
≥
0
be an
n
-dimensional standard Brownian mo-
tion and
J
an independent Poisson random measure
F
,
P
,
F
with associated
compensator
J
and intensity measure
ν
, where we assume that
ν
is a Lévy mea-
sure. We assume that the filtration is generated by the two mutually independent
processes
W
and
J
and that
W
and
J
are independent of
R
+
× R \{
0
}
F
0
.Let
d
:=
n
v
+
1bethe
d
, whose dynamics evolve according to the SDE
dimension of the process
Z
∈ R
ς
s
(Z
t
−
,ζ)J(
d
t,
d
ζ)
d
Z
t
=
b(Z
t
−
)
d
t
+
Σ(Z
t
−
)
d
W
t
+
|
ζ
|
<c
+
ς
l
(Z
t
−
,ζ)J(
d
t,
d
ζ).
(15.1)
|
ζ
|≥
c
d
d
,
Σ
d
d
×
n
,
ς
d
d
,
We assume that the coefficients
b
: R
→ R
: R
→ R
: R
× R → R
ς
are Lipschitz continuous and satisfy a linear growth condition: There
exists a constant
C>
0 such that for all
z, z
∈ R
∈{
ς
s
,ς
l
}
d
,
ζ
∈ R
b(z
)
Σ(z
)
z
|
|
b(z)
−
|+|
Σ(z)
−
|≤
C
|
z
−
,
|
b(z)
|+|
Σ(z)
|≤
C(
1
+|
z
|
),
(15.2)
ς(z
,ζ)
z
|
|
ς(z,ζ)
−
|≤
C(
1
∧|
ζ
|
)
|
z
−
,
|
|≤
∧|
|
+|
|
ς(z,ζ)
C(
1
ζ
)(
1
z
).
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