The By Operator graph shows all of the measurements taken in the study, arranged by operator. The measurements are represented by dots; the means by the circle-cross symbol. The line connects the average measurements for each operator.

Ideally,

·    the measurements for each operator will vary an equal amount

·    the part averages will vary as little as possible

For the parts data, this seems to be the case. There will always be some variation, but it appears the operators are measuring consistently. To be sure, check the Operator*Part interaction plot when determining whether operators are measuring similarly.