
Multi-asset stochastic volatility 431
ρ(bσ
2
T
, S
1
)/ρ(bσ
2
T
, S
2
)
over several maturities. Likewise, for the determination
of
χ
σσ
, two values are obtained by averaging either
ρ(bσ
1
T
, bσ
2
T
0
)/ρ(bσ
1
T
, bσ
1
T
0
)
or
ρ(bσ
1
T
, bσ
2
T
0
)/ρ(bσ
2
T
, bσ
2
T
0
), for all (T, T
0
) couples.
Note that it is important to use asynchronous estimators – lest we underestimate
correlations; see [12].
S&P500 Stoxx50 S&P500 Stoxx50 NIKKEI S&P500 Stoxx50 S&P500 Stoxx50 NIKKEI
Stoxx50 FTSE NIKKEI NIKKEI KOSPI Stoxx50 FTSE NI KKEI NIKKEI KOSPI
83% 89% 55% 60% 67% 71% 86% 45% 59% 66%
87% 95% 59% 63% 85% 78% 89% 56% 61% 108%
86% 93% 71% 78% 78% 75% 91% 53% 77% 65%
84% 92% 54% 60% 72% 72% 85% 31% 40%