APPLYING PRINCIPAL COMPONENT ANALYSIS TO A GR&R STUDY

ABSTRACT

The gauge repeatability and reproducibility (GR&R) study is typically conducted on a single quality characteristic. However, manufacturing tests in a GR&R study usually have multiple characteristics with a multivariate normal distribution. Principal component analysis (PCA) method can transform the multiple characteristics into one or a few irrelevant variables and provide sufficient information. Then, these irrelevant variables were analyzed using analysis of variance. Two composite indices such as precision to tolerance (P/T) ratio and measurement variation to total variation of measurement system ratio (σ² _gauge /σ² _Total ) combining from all variables were used to evaluate the adequacy for the measurement process. A real example was used to demonstrate the application of the proposed methodology.

Keywords:

• gauge repeatability and reproducibility
• multiple characteristics
• principal component analysis