-- 1.3. X-efficiency, and the neoclassical production and cost functions -- 1.4. The development of XE theory -- 1.5. XE …: Regulation theory and X-efficiency -- 3. X-efficiency: The intellectual setting and an introduction to the theory -- 3 ….1. Introduction -- 3.2. Complex objective functions -- 3.3. XE theory: An introduction -- 3.4. Conclusions -- 4. X-efficiency theory …