I am new to R. I am using package "PerformanceAnalytics" to calculate Component VaR of portfolio.
If I use gaussian method, it returns contribution.
> VaR(edhec, p=.95, method="gaussian", portfolio_method="component")
no weights passed in, assuming equal weighted portfolio
$VaR
[,1]
[1,] 0.01193358
$contribution
Convertible Arbitrage CTA Global Distressed Securities Emerging Markets Equity Market Neutral Event Driven Fixed Income Arbitrage
0.0014400703 0.0003687009 0.0012961865 0.0032090406 0.0003479361 0.0013848605 0.0010051944
Global Macro Long/Short Equity Merger Arbitrage Relative Value Short Selling Funds of Funds
0.0011151866 0.0015860006 0.0004412756 0.0009265836 -0.0027498306 0.0015623733
$pct_contrib_VaR
Convertible Arbitrage CTA Global Distressed Securities Emerging Markets Equity Market Neutral Event Driven Fixed Income Arbitrage
0.12067381 0.03089608 0.10861675 0.26890849 0.02915606 0.11604738 0.08423244
Global Macro Long/Short Equity Merger Arbitrage Relative Value Short Selling Funds of Funds
0.09344947 0.13290235 0.03697764 0.07764507 -0.23042800 0.13092245
>
But If I use historical method it just returns a single portfolio level value
> VaR(edhec, p=.95, method="historical", portfolio_method="component")
no weights passed in, assuming equal weighted portfolio
[1] 0.01439231
>
Is this correct? Am I missing something?
EDIT
I want to calculate component VaR of each part using historical simulation method.
Leaving off the
portfolio_method="component"
part returns all of the individual percent contributions.Results:
Though why that is, I'm not sure, as I'm not familiar with the package or VaR in general.
help(VaR)
does seem explicit to the behaviour. Not to my untrained eyes anyway.The 'historical' method is not a 'simulation' method. It is a measure of the realized historical loss quantile.
I have added historical contribution to
PerformanceAnaltytics
in v 1.4.3574 on R-Forge.Your example now produces:
It is available from SVN now, should be available in binary form 'soon', and will be included in the next release of
PerformanceAnalytics