Also (in the defense field) the practice of applying
economic modeling to
defense analysis problems, specifically those involving system performance and evaluation. Introduced by
SecDef Robert McNamara (a big-business executive) as a method (ostensibly) of better evaluating defense-related proposals.
However, in reality, it served mostly (as McNamara and cronies have since admitted) to obfuscate the actual process of evaluating systems, allowing McNamara's preferences to remain ascendant in decisionmaking. This is because it took the military services and other analysts some time to figure out just what the heck McNamara and co. were doing in their analyses, making it difficult to argue with them - winning arguments by obfuscation, essentially.
The RAND corporation was one of the chief purveyors of such studies. However, they actually managed to get the things mostly right, which is one reason McNamara and co. stopped 'liking' RAND studies.