The ability of futures markets to predict subsequent spot prices has been a controversial topic for a number of years. Empirical evidence to date is mixed; for any given market, some studies find evidence of efficiency, others of inefficiency. In part, these apparently conflicting findings reflect...

Monthly data on the $US/ECU exchange rate are analysed in light of the random walk hypothesis. A battery of tests, including procedures that are robust to conditional heteroscedasticity, are applied against linear alternatives to departures from the random walk. These tests are all based on the...