A behind-the-scenes blog about research methods at Pew Research Center. For our latest findings, visit pewresearch.org. Every survey finding published by Pew Research ...

Control charts that are properly constructed and maintained prevent false out-of-control signals and provide a useful method for monitoring a process. Process control is and has been an important ...

The extent to which products meet specifications needs to be systematically monitored in a production process. Product quality will typically be defined by two quantities: deviations from stated ...