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George Huxtable wrote:
> In fact, if any systematic errors have been properly corrected for,
> and only random scatter remains, the simple truth is this. Only on one
> time in 4 will the vessel be inside that triangle at all, and 3 times
> in 4 it will be somewhere outside it, though in the vicinity. This is
> a simple statistical truth, easily proved, but one that mariners are
> most reluctant to accept, because it is so contrary to what they have
> been taught.

George:

First of all, thanks for such an insightful post.  Like most, I've been
taught that a cocked-hat fix is a wonderful thing to have; that one must
surely be inside the cocked hat.  Even though I know enough of
statistics, I never thought of the statistics of a cocked-hat fix.

But now a question:  Is the probability that I'm inside the cocked hat
1 in 4 or 1 in 8??

I presume your "simple statistical truth" is that, absent any additional
information about the quality of the LOPs, there is a 50% chance that my
true position is on one side or the other of the LOP.

To be inside the cocked hat, it seems to me that I have to be on one
particular side of each of the LOPs, which makes for a probability of
1/2^3 or 1/8.

What am I missing?

Lu Abel

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