Abstract
The objective of the paper is to measure the intensity of the relation between expectations and realizations for strategic variables of firms, such as production, demand or prices. An anticipation error reveals a disagreement which can be associated with the rational expectations hypothesis. The agreement coefficient between classifications, given by COHEN (1968) and LIGHT (1971) and calculated from a probability matrix, is used to define a direct measure of the disagreement between classifications. Comparison of the coefficients is used to test the rational expectations hypothesis.The coefficients are applied to business survey data of INSEE for France between 1974 and 1986.