• Casey replied to the topic Mean or Variation. in the forum General 17 years, 12 months ago

    Every experience I have had with AHT is that in its basic form, looking at it from a per call basis and not an average of averages it is un-normal data skewed to the right.  On this note if you see a shift in your variation you will also see a shift in your mean since the median is your central point and your mean is not.  
    Where you choose to…[Read more]

  • Casey replied to the topic Which tool to [email protected]# in the forum General 18 years ago

    I am curious on how you would use a Chi Square test for a problem like this.  It seems that he is focusing on continuous data and I have always seen the Chi used with discrete data.  Are you recommending a change of the data before such a test?
    It is an fascinating choice of test for this type of data and I am interested in finding out ho…[Read more]

  • Casey replied to the topic Use of 1.5 Sigma Shift and 3.4 PPM in the forum General 18 years ago

    Motorola (aka Mikel Harry) does not have data showing that processes shift 1.5 standard deviations. If anyone can produce that data, I will of course, retract my claim and apologize. Harry’s original book describing the shift was based on two references, both of which show merely a theoretical calculation, and a simulation. He does not state the…[Read more]

  • Casey replied to the topic Six Sigma and the Sox in the forum General 20 years, 9 months ago

    Jack Welch never won squat in the front office.  Championships are won on the field.  The cost of front office operations is not directly correlated to team performance.  Commit to buying good players and wins will follow.  It’s a quick hit baby!