Tag
#variation
2 topics across all disciplines.
MSA and gauge R and R
Why a measurement is a process with its own variation, what repeatability and reproducibility separate, how to read a percentage study result, and why a gauge that passes on one tolerance fails on another.
SPC and process capability
Why control limits are not specification limits, what common and special cause variation demand differently, the difference between Cp, Cpk, Pp and Ppk, and why tampering with a stable process makes it worse.