Sub-additivity Re-examined: The case for Value-at-Risk
by Jón Daníelsson of the London School of Economics,
Abstract: This paper explores the potential for violations of VaR subadditivity both theoretically and by simulations, and finds that for most practical applications VaR is subadditive. Hence, there is no reason to choose a more complicated risk measure than VaR, solely for reasons of subadditivity.
Keywords: Value-at-Risk, subadditivity, regular variation, tail index, heavy tailed distribution.