Rick Pastor


  • Rick Pastor replied to the topic Probability in the forum General 18 years, 11 months ago

    What is too perfect is a good question and I thank the original author for the question.  I did test to see how things might look if I generated a histogram from numbers obtained randomly from a normal distribution; and A Shapiro-Wilk W test to determine normality.  I obtained the following results.
    N=   52    …[Read more]

  • Rick Pastor replied to the topic Variation in the forum General 18 years, 11 months ago

    Anonymous:  Let me tell you what I would do assuming that the following has not already been done.  Measure the 13 point (12 perimeter, 1 center), keeping track of their (x,y) position in the disk and the (x’,y’) position on the perimeter or (r,q).  You could make a series of contour plots that would give you a visual impact of the unifo…[Read more]

    Point 1:  A the top right hand side of this page there is a sigma calculator. 
    Point 2:  I “like” Logon Luo description of what you need to do.  I would like to add that you probably have more opportunities for creating a defect than three.  Each opportunity is a potential point of improvement.   
    Point 3: The calculation of a sigma le…[Read more]

    BOB WOW Interactions at What Sacrifice?  The following will show that a BOB WOW experiment “can” and “cannot” provide information on interactions but you have to make statistical sacrifices.  This sacrifices has not been mentioned in previous replies to the original message.  One pair of BOB WOW samples does not allow for an analysis of inter…[Read more]