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    Re: Still on LOP's (mea culpa)
    From: Rodney Myrvaagnes
    Date: 2002 Apr 26, 07:49 -0500

    Now I am getting confused anew. If the sigma is the same for each LOP,
    then how can the expression below weight dN differently from dM. All
    the d's are squared inside the exp(). So in a 3-LOP case, how could the
    center be anything but the center of the inscribed circle (i.e. all d
    the same value)?
    
    Plainly when more than 3 LOPs are in play, it is no longer an inscribed
    anything, so I guess the distinction is an accidental case, rather than
    anything fundamental.
    
    
    On Fri, 26 Apr 2002 00:48:07 -0400, Michael Wescott wrote:
    
    >
    >Given that each observation comes from the same Gaussian distribution
    >the joint probability density is proportional to
    >
    >        exp( -(d1**2 + d2**2 + d3**2 ... ))
    >
    >where dn is the distance from a point to LOP number n. So it's
    >a matter of minimizing d1**2 + d2**2 + d3**2 ...  to get maximum
    >joint prob density or MPP. In other words it's a least squares problem.
    >
    >So Steven Tripp, Trevor Kenchington et al. were correct that the MPP is
    >not the center of the inscribed circle.
    >
    
    
    Rodney Myrvaagnes                                  J36 Gjo/a
    
    
    "Curse thee, thou quadrant. No longer will I guide my earthly way by thee."  Capt. Ahab
    
    
    

       
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