Retrospectives: X-Efficiency
回顾哈维·莱宾斯坦1966年提出的X效率概念，即实际效率与理想配置效率之间的差距，以及他与乔治·斯蒂格勒的经典争论，对理解企业成本最小化假设的争议仍有启发。
In a 1966 article in the American Economic Review, Harvey Leibenstein introduced the concept of “X-efficiency”: the gap between ideal allocative efficiency and actually existing efficiency. Leibenstein insisted that absent strong competitive pressure, firms are unlikely to use their resources efficiently, and he suggested that X-efficiency is pervasive. Leibenstein, of course, was attacking a fundamental economic assumption: that firms minimize costs. The X-efficiency article created a firestorm of criticism. At the forefront of Leibenstein's powerful critics was George Stigler, who was very protective of classical price theory. In terms of rhetorical success, Stigler's combination of brilliance and bluster mostly carried the day. While Leibenstein's response to Stigler was well reasoned, it never resonated with many economists, and Leibenstein remains undeservedly underappreciated. Leibenstein's challenge is as relevant today as it ever was.