The empirical evidence of the Purchasing Power Parity (PPP) Hypothesis in the exchange rate market is examined by means of fractional integration analysis.

The seasonal structure of quarterly U.K. and Japanese consumption and income is examined by means of fractionally-based tests proposed by Robinson (1994). These series were analysed from an autoregressive unit root viewpoint by Hylleberg, Engle, Granger and Yoo (HEGY, 1990) nd Hylleberg, Engle,...

Multivariate tests of fractionally integrated hypotheses are proposed in this article. They are a natural generalization of the univariate tests of Robinson (1994) for testing unit roots and other nonstationary hypotheses.