double_decay: Flexible Probabilities using Partial Information
Description
Match different decay-factors on the covariance matrix.
Usage
double_decay(x, slow, fast)
# S3 method for default
double_decay(x, slow, fast)
# S3 method for numeric
double_decay(x, slow, fast)
# S3 method for matrix
double_decay(x, slow, fast)
# S3 method for ts
double_decay(x, slow, fast)
# S3 method for xts
double_decay(x, slow, fast)
# S3 method for tbl
double_decay(x, slow, fast)
# S3 method for data.frame
double_decay(x, slow, fast)
Value
A numerical vector of class ffp with the new
probabilities distribution.
Arguments
x
An univariate or a multivariate distribution.
slow
A double with the long half-life (slow decay) for the correlation
matrix.
fast
A double with the short-life (high decay) for the volatility.
References
De Santis, G., R. Litterman, A. Vesval, and K. Winkelmann, 2003,
Covariance matrix estimation, Modern investment management: an equilibrium
approach, Wiley.