The commenter offers three criticisms of the suggested weighted variance (WV) method in the paper by Choobineh and Ballard (ibid., vol.R-36, p.473-7, Oct. 1987), although agreeing that the method, ...

Statistical Process Control (SPC) is the use of statistical tools and techniques to analyze a process or its outputs to control, manage, and improve the quality of the output or the capability of the ...

Here’s how control of the House and Senate have shifted over the past 120 years: * Democrats controlled the House with a coalition formed with the Progressive and Socialist parties.