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    Re: A slope example
    From: Antoine Couëtte
    Date: 2010 Dec 4, 10:15 -0800

    Dear Piterr,

    In further reply to both of your posts :

    [NavList 14610] Re: A slope example, dtd 4 Dec 2010 09:01, and

    [NavList 14616] Re: A slope example, dtd 4 Dec 2010 12:58,

    you kept inquiring about an unexplained discrepancy between my VEGA shots values and their averaged value, as quoted in my earlier post [NavList 14514] Re: A slope example, dtd Nov 26, 08:13.

    You will find here-after the explanation to this apparent discrepancy.

    Please be so kind as to closely read my [NavList 14514] post again. You will find that :

    - The 5 (UT, Sextant Heights) - i.e. TOPOCENTRIC observations INCLUDING THE EFFECTS OF REFRACTION - have a (quoted) average of ( 16h30m11.060s , 69d12.28m ) which falls EXACTLY IN THE MIDDLE OF ALL OTHER OBSERVATIONS. You also find that

    - The 5 (UT, GEOCENTRIC HEIGHTS) have a quoted average of ( 16h30m11.060s , 69d04.213m) . Therefore the mean height of 69d04.213m is the GEOCENTRIC HEIGHTS AVERAGE.

    In your graph you have displayed both the individual TOPOCENTRIC HEIGHTS, while you have altogether plotted the averaged GEOCENTRIC HEIGHT.

    In other words, yo are comparing a first set of measures (the TOPOCENTRIC one) with the mean value of a different set (the GEOCENTRIC one).

    It explains why you observe this very obvious discrepancy.

    Thank you for your kind attention and Best Regards


    PS : For the help and interest of all other readers, please be so kind Piterr as to use plain English - whether US American or UK English as you see fit ... :-)) - in accordance to the most usual and standard guidelines as recently indicated by Frank E. Reed, which - most contrarily/in opposition to your own advice here - I personnaly find quite right, reasonable and well balanced. Certainly if you want to write in French, and yours is absolutely perfect as I can read it, please be so kind as to use my own personal e-mail address (antoine.m.couette*club-internet.fr, with * standing for arobace here).
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