Commodity price volatility in international markets has been used to justify numerous policy interventions, including the need for buffer stocks and counter-cyclical payments. The common measure of volatility, the standard deviation or coefficient of variation, likely overstates the actual...

The European sovereign debt problem became the focus of world attention in 2010, when the interest rates on Greek government bonds rose dramatically, requiring immediate action by the European Union to avoid an imminent default. It has become clear that the problem is not limited to Greece, but...