Robert Butler


  • @rbutler brings up excellent points.

    See if you can quickly change your measurement system to a variable/continuous data system and confirm it’s performing with an MSA. You’ll solve your problem well and faster and learn more about the process if you are able. 3 months ago

  • @rbutler Robert, as usual, a concise simple to understand explanation LOL. I always learn so much from your posts…at least the parts that I understand. Hope all is well. 4 months, 3 weeks ago

  • @rbutler thanks again!
    But why can’t I use Dunnett’s test if my purpose is to find a factor or combination of factors to optimize for max success rates?

    I have done Tukey test, and it shows the same, that A factor is significant compared to Control. However,  A1B0 vs A1B1 is not.

    Does it mean that in this case of logistic regression results of…[Read more]

  • @rbutler thank you for your reply!

    Number of trials is actually number of time each treatment ran, for example for A0 B1 there was 7539 runs and in 141  cases there was a success for count2 response and 93 successes for count response. I am considering now only count2 response for the analysis though.

    I rewrote it in R to be a bit more clear:


    [Read more]

  • @rbutler – a function of the computer generation.  If they had grown up with a slide rule, they would understand.  ;-) 9 months, 4 weeks ago

  • @derekkoz – as the learned @rbutler identifies, once you limit the number of decimal places you are going to use, you have created a discrete measure.  The key is whether the number of decimals is sufficient to provide the resolution needed to answer the question being investigated.  Now, don’t get me wrong, there are certainly absolute discrete m…[Read more]

  • It seems you do have a UCL. :)

    hope all is well with you @rbutler ! 10 months, 2 weeks ago

  • @rbutler you are kind to help with homework. :)

    Stay safe and hope your family stays well! 11 months, 2 weeks ago

  • Thanks @rbutler for you time :-)

    “What your post does suggest is you have some understanding of why coils are rejected.  For example, you mentioned dark surface on wire is cause for rejection….and what else?”

    In fact it is his department’s process where coils are wet-processed such as degreasing and then coils go for the inspection before de…[Read more]

  • @rbutler

    Fantastic Idea Robert (in the file) 1 year ago

  • @rbutler – Big Brother is always watching ;-} 1 year ago

  • @rbutler – and simple algebra at that ;-) 1 year ago

  • @irfan.ahanger01 – I’m certainly not going to disagree with @rbutler (good to see you’re still here, trying to educate the masses!), but I would take a more pragmatic approach.  You already have a design with the center points, so you need to add the Star Points.  For each factor, you will need two – a high and a low, set at an alpha level – to a…[Read more]

  • @rbutler and @darth — If you look at the newsletter, I’ve been sharing “Classic iSixSigma” discussions the past couple of weeks. This is one of them.

    As for any others, one was spam that I deleted as soon as I saw it. 1 year, 3 months ago

  • @rbutler  Glad it isn’t just me.  People must be so bored that they are getting back onto (LOL) and so desperate for something to do they are responding to decade old posts.  Next might be responses to test questions or dissertation topics from people who graduated a decade ago.  We might even see someone pop in to comment on the…[Read more]

  • This attached planning sheet helps me to focus.  I hope it helps you too!


    If you combine completing it with the help @rbutler has provided you should be in the right area! 1 year, 3 months ago

  • @Timmaaay I don’t normally say anything after Robert @rbutler posts because when it comes to the numbers you aren’t going to get better advice that what you get from Robert. He has this down pretty solid and he understands application not just theory.

    I am not trying to make excuses for who ever wrote the WI. You might want to check out the…[Read more]

  • Thanks a lot @rbutler

    I have found some references you mentioned and I will use them.


      1 year, 4 months ago

  • Thanks for your reply @rbutler.

    I think some parts of my previous post was not clear.

    I need to mention I can change my “stiffness” or “pipe motion” values, but the provided values (such as 5,10,100,500,1000,5000 for stiffness and 1.2,1.5,1.8,2.4,2.7,3,3.3,3.6,3.9,4.2,4.5 m for pipe motion) are my critical points and I want to use these data to…[Read more]

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