Balanced Information: The Pickering Airport Experiment
以加拿大皮克林机场争议为例，探讨公共政策评估中如何确保信息平衡，避免研究资源过度集中于一方，并介绍了一种通过模拟决策过程来检验信息平衡性的实验方法。
IN March of 1972, the Canadian federal government and the Ontario provincial government jointly announced that a second international airport for Toronto would be built near the town of Pickering, Ontario. Considerable controversy followed this decision in spite of the great number of governmental studies on which the decision had presumably been based. Among other criticisms it was alleged that while the government's research effort had been extensive, it had not necessarily been balanced, and the case for simply expanding the existing international airport at Toronto might have been understated. The problem faced by the Canadian government in this instance illustrates a frequent problem in the evaluation of public policy alternatives: how to provide balance in the development of information so that both the pro and con positions can be said to be adequately represented. Airport location studies provide particularly good illustrations of the problem of balance because it is impossible for the data and arguments ever to be considered complete. No matter what the expenditure of time and money, there is always room for further research. Even after the million-pound Rosskill cost-benefit study regarding the third London airport, Mishan (1970) and Flowerdew (1972) describe how differences of opinion continued to persist among economists on the commission itself. Similarly, for the Pickering Airport question, no amount of study could be expected to be definitive. In such cases the problem of how to assure that resources and talent are not overconcentrated on one side or the other is a problem of importance. The response of the Canadian government to the Pickering controversy was to appoint a three-man review board, headed by a federal judge, to serve as an Airport Inquiry Commission. The commission was assigned full responsibility for reviewing existing airport studies, holding new hearings, and presenting new summaries and recommendations regarding whether or not the new airport should be built. The procedure chosen in this instance illustrates a common approach to organizing information for decisions. A group such as an executive or legislative committee wishes to receive both balanced information and recommendations regarding some proposal, but allows the same people who are asked to make the recommendations to also summarize the information. When the group making the recommendations also summarizes the information, however, the balance in this information is subject to question. The information may be seen in part as a rationale for the recommendations, and both the information and recommendations may be considered too dependent upon the personal views of a small group. Consequently there have been suggestions for more formal information procedures for certain executive and legislative decisions. More formal information procedures, for example, have been proposed for government technology assessment. As one example, Uman (1975) outlines procedures for using science advisory panels as checks on internal government technology assessments. Other technology assessment procedures are surveyed in articles by Jones (1973) and Coates (1974). An even more formal approach to securing balance in information is the Science Court proposed by Kantrowitz and discussed in reports such as that by the Task Force of the Presidential Advisory Group in Anticipated Advances in Science and Technology (1976). The Science Court and many of the other formal procedures for balance, howReceived for publication March 20, 1978. Revision accepted for publication August 8, 1980. * York University. This study was supported by the University of TorontoYork University Joint Program in Transportation and Canada Council Grant No. 770121. The author would like to thank R. F. Boruch, H. 0. Hartley, B. L. Raktoe, and also the participants at the 1978 National Bureau of Economic Research-National Science Foundation Conference on Decision Rules and Uncertainty at Carnegie-Mellon University. The author is particularly indebted to the economists who formed the research teams for the experiment, John Evans with advisor George Hilton, and Sanford Borins with advisor Glen Jenkins. Finally the author would like to acknowledge useful suggestions from the referees.