Abstract: | Time series behavior of monthly spot exchange rates for the French franc, the Deutsche mark, the Italian lira, the Japanese yen, and the UK pound, all priced in relation to the US dollar, shows the robustness of the random walk hypothesis. Incremental efficiency is investigated by a new test procedure, based on the reduction of the forecast error variance, which is a direct implementation of the definition of Granger causality. Exchange markets are found to be not only money efficient, but also monetary efficient in that they are efficient with respect to real income and market interest rates in addition to money stock. |