Bill Mc


  • Primarily because it is in line with what I have done and taught over the years. I was introduced to the mechanics of SPC way back in 1983. In reality, I have never liked Gage R&R studies because they are simply a snapshot in time of a measurement system – whether you are using the average and range method or ANOVA. Unless the measurement…[Read more]

  • Stan, thanks for giving the details of your objections/concerns about his article. It makes it easier to understand where you are coming from on his much to do about nothing. Also, it provides much more information for the readers in this forum.

  • Yes, my customers use Excel and even Minitab – which contains the average and range method. Dr. Wheeler’s paper is well-written. I believe Darth asked you and others for a take on Dr. Wheeler’s position. You give no specifics except that, because he addresses the average and range method, it is much to do about nothing. What in the paper is not…[Read more]

  • Yes, I do know something about the subject. I would estimate that 75% of the questions I get from customers using gauge R&R are about the average and range method and the questions usually indicate that the customer has no idea what they are doing. They just want something to tell them that their measurement system is good – even when it…[Read more]

  • I think it is well written and points out the issues associated with the average and range method that is in the AIAG Measurement Systems Analysis manual. His point is simply that the variances are additive, not the standard deviations. Many companies still use the average and range method and wonder why their results are poor – when it fact,…[Read more]