Cartels Uncovered
利用芬兰制造业1951-1990年卡特尔合法时期的数据，通过隐藏马尔可夫模型估计卡特尔的存在与持续时间，发现卡特尔一旦形成便持续存在，到期末几乎所有行业都被卡特尔化。
How many cartels are there, and how long do they live? The answers to these questions are important in assessing the need for competition policy. We present a Hidden Markov Model that takes into account that often it is not known whether a cartel exists or not. We take the model to data from a period of legal cartels—Finnish manufacturing industries 1951–1990. Our estimates suggest that once born, cartels are persistent; by the end of the period, almost all industries were cartelized.