This project investigates how scientists drawing on three disciplines -- economics, statistics, and control engineering -- shaped a new applied mathematics as researchers designed mechanisms for warfare that controlled rather than simply recorded. Norbert Wiener described the contrast in what these scientists sought as that between new mechanisms in the "imperative mood" versus earlier devices that operated in the "indicative mood." The significance of the shift is broad. In the course of designing physical devices in the imperative mood, researchers constructed mathematical models and algorithms that social scientists later appropriated. As they were passed between engineering and economic applications, similar models took on deterministic, stochastic or adaptive forms. The process of solving problems for a military client, which involved reasoning with physical analogies and tailoring the solution process to computational resources, changed the use and construction of models in applied mathematics, and ultimately changed the idea of what was a solution to an applied mathematical problem. By 1960, the imperative mood had spread beyond the devices under initial study to the analytical disciplines themselves.
Through cases of specific mathematical protocol, Klein uses World War II and cold war documents in the National Archives, the RAND Corporation Archives and the Economist Papers at Duke University to investigate the transformation in economics, statistics and control engineering to modeling optimal, multistage decision processes. These protocols include sequential analysis, exponentially weighted moving averages, optimal inventory control, dynamic programming, the Kalman filter, and adaptive models in general. In addition to researching the material origins of these model and algorithms, Klein examines the stages of formulation, user needs, media, and government financing that stimulated their diffusion to the managerial and social sciences.
Outcomes of the research include a monograph, pedagogical examples for undergraduate courses in applied statistics and economics, and a treatment, of the case of the exponential smoothing circuit in lead gun sights, for consideration by the Public Broadcasting Service.
