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    Re: The Darn Old Cocked Hat vs CG?
    From: Andrés Ruiz
    Date: 2013 Mar 19, 19:59 +0100
    Hello Hanno,
    You wrote: Is there an counter example, one in which my choice of the TL would be far outside that ellipse?
    ...
    No the fix is the MPP, most probable position, and the ellipse of confidence is centered on it. Why?, because is based in real observations, no random data. With an associated probability to be inside proportional to the area of the ellipse and inversely to the number of observations.

    In your random model the high prob is near the true position, but a priori is not known.
    And I insist each theoretical model must be validated against real data.

    Regards

    2013/3/19 Hanno Ix <hannoix---.net>

    Andres:

    My rough-and-ready approach predicts the TL 2/3 down the median
    as seen from the vertex (iow: at the CG) which it is - or at least rather close.
    In your diagram, it certainly is within the 99% ellipse.

    Could this be just a random coincidence? 
    Is there an counter example, one in which my choice of the TL would be far outside that ellipse?
    If it is not by coincidence then the probability of its being within the Doch must be bigh.

    Regards

    h


    From: Andrés Ruiz <navigationalalgorithms---com>
    To: hannoix---net
    Sent: Tuesday, March 19, 2013 6:59 AM
    Subject: [NavList] Re: Cocked hat vs Confidence ellipse


    An example for 4 LoPs: see the attached animation for the ellipse of conficence of 25% 50% 75% 95% and 99% prob.

    Error:
    S = 0.0011
    sigma = 1.3999
    sigmaB = 1.0029
    sigmaL = 1.0499

    Ellipse:
    Prob = 0.01 0.25 0.5 0.75 0.95
    k = 0.1418 0.7585 1.1774 1.6651 2.4477
    theta = 40.0289 40.0289 40.0289 40.0289 40.0289
    a = 0.1637 0.876 1.3598 1.9231 2.8269
    b = 0.1248 0.6675 1.036 1.4652 2.1539

    --
    Andrés Ruiz
    Navigational Algorithms
    http://sites.google.com/site/navigationalalgorithms/
    Attached File:


    View and reply to this message: http://fer3.com/arc/m2.aspx?i=122954


    View and reply to this message: http://fer3.com/arc/m2.aspx?i=122955




    --
    Andrés Ruiz
    Navigational Algorithms
    http://sites.google.com/site/navigationalalgorithms/
       
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