This study re-evaluates the validity of the joint rational expectations-permanent income hypothesis under the framework of seasonal cointegration using seasonally unadjusted quarterly data from Austria, Canada and Taiwan. Evidence is found that the consumption change only depends on the innovations of the income and the unemployment rate changes, and that agents are rational in forming their expectations, i.e., the joint hypothesis is supported by the data used. However, with the same data set, a similar test based on non-seasonal cointegration tends to reject the joint hypothesis, since the test ignores completely the possible stochastic seasonalities that may contain important information, as has been pointed out by Wallis (1974), embodied in the data.
