Measurement System Analysis: repeatability, reproducibility, and fitness for use.
Gage R&R (Gage Repeatability and Reproducibility) and Measurement System Analysis (MSA) evaluate whether your measurement system is adequate for process control and product decisions. Repeatability is variation when the same operator measures the same part multiple times; reproducibility is variation between operators (or appraisers). I use MSA to qualify new gages, validate measurement processes, and support SPC and process capability studies so that quality systems rely on trustworthy data.
AIAG-style Gage R&R studies (crossed or nested designs), %GRR vs. tolerance or study variation, and ndc (number of distinct categories) are standard outputs. I design studies, analyze results in Excel or statistical software, and recommend actions when %GRR is too high.