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    Re: Are we most likely not where we are?
    From: Brian Whatcott
    Date: 2002 Apr 15, 09:23 -0500

    At 08:27 AM 4/15/02, Bill Murdoch wrote:
    >In a message dated 4/15/2002 12:06:50 AM Eastern Daylight Time,
    >hprinz@ATTGLOBAL.NET writes:
    >most probable position (MPP) is, by definition (!), inside the cocked hat.
    >I am not so sure about that.  I think it may be true if the errors are
    >random, but not if they are not. Let's say I have three bodies at 300,
    >000, and 060 degrees (the horizon is dirty to the south), and a sextant
    >with an (unknown to me) 5 arcminute error.  I reduce my sights, get a nice
    >small cocked hat and am actually 5 miles to the same side of all three
    >LOPs.  It seems to me that my most probable position is outside the cocked
    >hat.  Now these are non-random errors, but those are the pretty normal (at
    >least for me).
    >Bill Murdoch
    The argument against, goes like this: If I experience systematic errors
    that are material, I can compensate for them, in the long run. I am then
    left with random errors which are reasonably handled with probability
    ideas, served reasonably well by a cocked hat.
    If I allow a material systematic error to continue uncompensated, shame on me.
    Brian W
    Brian Whatcott
       Altus OK                      Eureka!

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