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    Re: Usefulness of the slope technique
    From: Peter Fogg
    Date: 2009 Aug 10, 21:51 +1000

    George Huxtable wrote:
    A simple plot of Jermy's data "Moonlines, Moon away from LAM" shows
    that the observation at 8.54.56 is a real misfit, and should be discarded.

    Discarding it has much the same practical effect as retaining it, if the problem causing it to appear as a "real misfit" can be resolved and corrected.

    and the only safe procedure is to delete that line. 

    The unsafe procedure, it would appear, is to accept uncritically data points (sights); to treat them as all equally valid, since as has been pointed out, one "real misfit" can significantly skew otherwise sound results.  This is a crucial difference between use of the slope technique and averaging, with which it tends to be erroneously confused. 

    On another topic George has admitted recently:

    "A few minutes ago, I posted the following, in which there was a silly error.
    It doesn't (I think, at first sight) affect the conclusions, but that will
    call for a bit more thought."

    I wonder if George might also consider whether his earlier somewhat glib conclusions as to this matter could also benefit from a: "bit more thought" ?





     

     


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