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Re: On LOPs
From: Steven Wepster
Date: 2002 Apr 16, 15:29 +0200
From: Steven Wepster
Date: 2002 Apr 16, 15:29 +0200
Hi, Let me add one cent. I don't understand what _the_ _true_ form of a confidence region should mean. IMO a confidence region is a region that contains the MPP with a specified probability, often taken as 95%. It can be circular, elliptical, square, heart-shaped or whatever you prefer, for whatever theoretical, practical, or other reasons are important to you. I have no references at hand now, but I remember there is a chapter on statistical navigation in Bowditch (at least in my eighties edition). I've never read it because I know I will never figure out an error ellipse in a force six on a dark night in Dover Strait. Steven. ----------------------------------------------------------- Steven Wepster wepster@math.uu.nl tel +31 30 253 1531 Mathematisch Instituut Universiteit Utrecht PO Box 80.010 3508 TA Utrecht The Netherlands =========================================================== >With respect, you have not advanced any logical reason why these >confidence intervals should be elliptical and (as I implied yesterday) a >brief graphical examination of the problem suggests that they are not >once there are more than two LOPs involved. What you appear to have is a >programmed version of some (unknown and thus unverifiable) equations >that calculate an elliptical approximation to the true shape of the >confidence interval. That makes yours one step more realistic than an >assumption that the area of uncertainty is circular but it does not >demonstrate that the true confidence intervals are elliptical.