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Re: The Darn Old Cocked Hat - the sequel 1
From: Hanno Ix
Date: 2013 Mar 12, 23:44 -0700
From: Hanno Ix
Date: 2013 Mar 12, 23:44 -0700
Gary:
Thanks for those copies!
With them you have answered the first question, and personally I agree.
Now to the second question. FER has stipulated that only *absolut* distances (errors) of the fixes from
the announced position are going to be considered for the competition, the azimuths will be ignored.
So he will rank all entries as to their fix error in sm from the location announced by
T. Cruise.
He might put them in ascending order and, of course, the one on top is the winner.
(He will receive a sparkling and working MHR1 donated by the Navy of the Federal Republic of Germany! )
Since FER is a passionate navigator, he wants to know more: frequency of errors over size of errors.
He will establish a row of buckets: 1. bucket for, say, 1 sm error, the next for 2 sm and so on to maybe
to the 20th for the ones with a 20 sm error.
Next he will put the entries into the appropriate buckets, i.e. each entry into the bucket that is labeled
with the error made by that entry. Of course, the whole thing is a histogram.
My 2. question asks: what curve will the contents of the buckets follow when the buckets are lined up?
Actually: What might the curve "error *frequency* vs error *size* " look like?
Note: that curve is just a 2D diagram, frequency (Y) vs size (X), not a 3D world with a surface of
frequency (Z) vs. lat (X), Long (Y). As you can see, the latter is the one we already considered in the prior question.
One thing is clear from the beginning: the curve we are looking
for will only have a positive X axis and a positive Y axis
simply because frequency and absolute size are both positive.
Again: What curve, do you think, will the contents of the buckets follow? No math, just a rough sketch!
Thank you for participating in this puzzle.
h
From: Gary LaPook <garylapook@pacbell.net>
To: hannoix@att.net
Sent: Tuesday, March 12, 2013 9:06 PM
Subject: [NavList] Re: The Darn Old Cocked Hat - the sequel 1
To: hannoix@att.net
Sent: Tuesday, March 12, 2013 9:06 PM
Subject: [NavList] Re: The Darn Old Cocked Hat - the sequel 1
Assuming no error in the true position announced by Tom Cruise (presumably from a GPS) the distribution should look like those in appendix Q of Bowditch. http://fer3.com/arc/imgx/HO-9-1977-Appendix-Q.pdf http://fer3.com/arc/imgx/Figure-Q6d_0001.pdf http://fer3.com/arc/img/114399.extended%20table%20q7d.pdf http://fer3.com/arc/m2.aspx/Accuracy-sextant-observations-sea-LaPook-nov-2010-g14399 If it is a two body fix with the LOPs crossing at 90° it should be a circle and if they cross at a different angle then it should be an ellipse. The size of the ellipse (or circle) will be based on the average standard deviation of the observers. gl --- On Tue, 3/12/13, Hanno Ix <hannoix---net> wrote:
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: http://fer3.com/arc/m2.aspx?i=122823