Colleen McKendry, Senior Statistical Writer, JMP Group Inc
This presentation is an extension of a case study presented at a Discovery conference a few years ago, where a client’s protocols required a Gauge R&R study to be performed before running a functional response designed experiment. As in a standard Gauge R&R study, there were several Parts, several Operators, and several replicates per combination of Part and Operator. However, in this case, the test equipment returned a set of curves as the response instead of a single point. A functional random effects model is appropriate for this type of data. In this application, the functional model is expanded using basis splines and then expressed as a mixed model, where variance components can be estimated using standard methods. This is done using the Functional Data Explorer and Fit Mixed platforms. Due to the functional model expansion, multiple variance components may be associated with each of the Part, Operator, and Part*Operator terms. It is shown that these variance components can be summed and written in the form of a standard Gauge R&R computation, therefore providing a Functional Gauge R&R analysis.
