Tacit Co-Ordination and Imperfect Information

The paper argues that tacit collusion is rendered more difficult by factors that make it harder for firms to observe rivals' behaviour and to infer their behaviour from currently available data. These difficulties arise from a combination of buyer concentration, randomness in demand, and lags between the action and its market impact. These hypotheses, tested on a sample of Canadian three-digit industries, appear to be consistent with the data. Coordination tacite et information imparfaite. Ce memoire suggere que la collusion tacite est plus difficile 'a proportion des difficultes qu'il y a a observer le comportement des rivaux et a inferer leurs comportements a partir des donnees generalement disponibles. Ces difficultes emanent d'un ensemble de facteurs: le degre de concentration des acheteurs, le caractere aleatoire de la demande, et les delais entre une action et son impact reperable sur le marche. Ces hypotheses son confirmees par les resultats d'une analyse d'un echantillon de 84 industries canadiennes.