It is crucial to understand the proper variance estimator in statistical process control (SPC) when you are trying to answer the questions on the process behavior both in the short term and the long term. In this paper we will discuss various variance estimators including their calculation using range and/or range squares, their potential use in SPC, their similarities and differences.
Date of creation, presentation, or exhibit
Department, Program, or Center
Holmes, Donald and Mergen, A. Erhan, "Integrating several variance estimators" (2005). Accessed from
RIT – Main Campus