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    Re: Cocked hats, again.
    From: Peter Fogg
    Date: 2007 Mar 21, 07:19 +1100

     Nicol�s wrote:
    > The standard deviation is only predicting 68% of the error (assuming it
    > is Gaussian). So if the standard deviation is for instance 20 arcseconds
    > it only means that there is a 68% chance (or 68.27% to be more precise)
    Or about 70% to be imprecise!
    > that the observation is within 20 arcseconds of the actual position. In
    > order to get 95% probability you need to multiply the standard deviation
    > by 2 (or 1.96 to be accurate, 2 will give 95.45%),
    Again, I kept it simple at about 90%
    Nicol�s, thanks for implicitly confirming my general idea: that by
    constructing these shadow LOPs the larger shape can offer an
    overwhelmingly large chance of containing the position, rather than
    the alleged 25% chance offered by the original LOPs. The other general
    idea I am hoping to show is that the position is overwhelmingly likely
    to lie close to the LOPs; each LOP is an approximation of the
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