By: |
Trojan, Sebastian |
Abstract: |
WA multivariate stochastic volatility (MSV) model based on a Cholesky-type
decomposition of the covariance matrix to model dynamic correlation in the
observation and transition error as well as in cross leverage terms is
proposed. The empirically relevant asymmetric concept of cross leverage is
defined as a nonzero correlation between the ith asset return at time t and
the jth log-volatility at time t+1. Volatilities and covariances are modeled
separately, which makes an interpretation of leverage parameters
straightforward. The model is applied on a three-dimensional portfolio
consisting of the S&P 500 sector indices Financials, Industrials and
Healthcare, spanning the recent financial crisis 2008/09. During and in the
aftermath of market turmoil, increased cross leverage effects, higher
unconditional kurtosis and stronger correlated information flow are observed.
However, there is risk of overfitting and restricting time variation to
elements governing dynamics of the observation error may be advisable. |
Keywords: |
Multivariate stochastic volatility, dynamic correlation, cross leverage, Cholesky decomposition, nonlinear state space model, Markov chain Monte Carlo, block sampler, particle filter |
JEL: |
C11 C15 C32 C58 |
Date: |
2014–08 |
URL: |
http://d.repec.org/n?u=RePEc:usg:econwp:2014:24&r=ets |