Keywords - Function groups - @ A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Library: VaR
See also: VaRDGdecompG DGdecompS

Quantlet: VaRDGdecomp
Description: uses a generalized eigenvalue decomposition to do a suitable coordinate change. The new risk factors are independently standard normal distributed and the new Hessian matrix (Gamma) is diagonal.

Reference(s):

Link:
Usage: r = VaRDGdecomp(l)
Input:
l a list with components: Delta - (m x 1) vector of first derivatives Gamma - (m x m) Hessian matrix Sigma - (m x m) covariance matrix
Output:
r a list with the additional components: B - (m x m) BB' = Sigma delta - (m x 1) first derivatives w.r.t. new coordinates lambda - (m x 1) diagonal of the Hessian matrix w.r.t. new coordinates

Example:
library("VaR")
library("xplore")
Delta = #(1,2,3)
Gamma = matrix(3,3) + 9*unit(3)
Sigma = unit(3)
l     = list(Delta,Gamma,Sigma)
VaRDGdecomp(l)

Result:
Contents of r.Delta
 [1,]        1
 [2,]        2
 [3,]        3

	Contents of r.Gamma
 [1,]       10        1        1
 [2,]        1       10        1
 [3,]        1        1       10

	Contents of r.Sigma
 [1,]        1        0        0
 [2,]        0        1        0
 [3,]        0        0        1

	Contents of r.B
 [1,]        1        0        0
 [2,]        0        1        0
 [3,]        0        0        1

Contents of r.lambda
 [1,]        9
 [2,]       12
 [3,]        9

Contents of r.delta
 [1,]  -1.2247
 [2,]   3.4641
  [3,] -0.70711



Author: S. Jaschke, 20021103 license MD*Tech
(C) MD*TECH Method and Data Technologies, 05.02.2006