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    Re: Lunars with SNO-T
    From: Alexandre Eremenko
    Date: 2004 Oct 26, 19:34 -0500

    Dear Fred,
    
    On Tue, 26 Oct 2004, Fred Hebard wrote:
    
    > But if you reject observations often, especially more than
    > one per session, I would say this is not a good idea
    
    Agreed. I was talking of that particular series only.
    
    > So it was a borderline case,
    > but one where conventional wisdom says rejection is OK.
    
    Borderline by the standard deviation criterion.
    But there are other criteria for rejection (besides
    convential wisdom).
    
    In a series where the distance SHOULD INCREASE (this I knew
    in advance, of course),
    and 5 of the 6 observations clearly follow increasing pattern
    but one does not (and substantially!) this one had to be rejected.
    If one accepts this one
    (I am always talking of my particular series of numbers!)
    one had to reject the TWO previous ones.
    
    This was my (almost unconscious) argument.
    I did not compute any standard deviations. This was just
    plane common sense.
    On the other hand (as a scientist:-) I carefully recorded it
    to be able to reduce it separately when needed.
    
    Maybe this also has some psychological explanation.
    When I said that some people "never make blunders",
    this was an exaggerration of course. I don't think
    there are such people indeed:-) But every reasonable
    person probably knows somehow (maybe unconsciously)
    HOW LIKELY s/he is to commit a blunder in such and such situation.
    My own feeling of this is based on my practice,
    and I know how frequently I misread the scale, copy a digit
    wrongly, add a correction instead of subtracting it, make a misprint,
    and
    so on.
    
    My second series of Lunars
    Mon Oct 25 2004 - 22:46:20 EDT  also shows that I estimate the
    likely magnitude of my random measurement errors correctly.
    
    Alex.
    
    
    

       
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