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Re: Position lines with confidence weights
From: Bill Lionheart
Date: 2018 Oct 26, 06:33 +0100

From the desk of the navigation-made-complicated department:

So what is the generalization of the symmedian point when there are
errors in each line have different variances? The answer is in

R. Stansfield, “Statistical theory of DF fixing,” Journal of the
Institution of Electrical Engineers-Part IIIA:
Radio communication, vol. 94, no. 15, pp. 762–770, 1947.

He defines a kind of weighted symmedian line and these intersect at
the weighted least squares point. One might think analogously of a
weighted centroid of a triangle with different masses at the vertices.

OK so we have computers and calculators to do it now but in principle
it could (have) be done graphically.

Bill Lionheart

On Sat, 20 Oct 2018 at 00:24, Antoine Couëtte  wrote:
>
> Enter twice the noon sight and once only each of the other observations.
>
> Then push the button and get the answer.
>
> Antoine
>
>

File:

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