GMS 401 Lecture Notes - Lecture 8: Central Tendency, Process Control, Statistical Process Control
Document Summary
Monitor by taking measurements and corrective action as a product or service being produced: variability is inherent in every process. Special or assignable causes: provides a statistical signal when assignable causes are present, detect and eliminate assignable causes of variation. For any distribution there is a measure of central tendency and dispersion. If the distribution of outputs falls within acceptable limits, the process is said to be in control. Can be traced to a specific reason. Objective is to discover when assignable causes are present. Constructed from historical data, the purpose is to help distinguish between natural and and assignable variations. Process control: in a statistical control and capable for producing within control limits (best, in a statistical control but not capable of producing within control limits, out of control and out of statistical control (worst) Variables: characteristics that can take real numbers (- infinity to + infinity, whole or fractional numbers, continuous random variables.