On the Use of Long-Term Risk Measures as an Approach to Communicating Risks

Value at risk (VaR) is a widely used measure for financial risks. However, as argued in Taleb (2012), “VaR encourages low volatility, high blowup risk taking which can be gamed by the Wall Street bonus structure.” It was also argued that one reason for this is the limited ability of all quantitative risk measures (including VaR, TVaR and many other modifications) to measure the risk of extreme events (black swans). In this paper, we argue that VaR and its modifications, being short–term in nature, intend to measure extreme risk by creating extreme small probability values. Even if accurate, they might not be effective in communicating risk to people because it is well documented in the psychology literature that humans tend to make irrational decisions when dealing with extreme small probabilities. As such, we propose that long-term risk measures, such as ruin probabilities over a long time horizon, provide a natural approach to avoid small probability values in measuring the risk of extreme events. They could be considered as a vehicle to communicate extreme risks to fund managers, insurance companies, as well as the public, and to help them in making decisions under uncertainty.