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    Re: Linear regression and other tools
    From: Bruce Cutting
    Date: 2018 Oct 14, 12:45 -0600

    Sure - I agree that the data will change depending on the declamation.
    But how would that affect the regression calculations - it would affect
    the resulting 2nd order curve coefficients but the calculations would
    remain the same - true ???  The accuracy or the resulting average would
    also be affected - if, in fact, the curve is of higher order than 2, the
    error of the average would be expected to be larger.
    On Sat, October 13, 2018 21:01, Ron Jones wrote:
    > The length of time prior to or after meridian transit that the rate of
    > change in the altitude of a body can be considered linear is strongly
    > influnced by the difference in the bodies declinaltion and the latitude
    > of the observer.  For example on October 13 2018 when the Sun's
    > declination is approximately 8 deg. South,  consider the Sun's altitude
    > vs time as viewed from latitudes 10N, 20N, 40N, 60N & 80N (see attached
    > PDFs).
    > Ron      48N   123W
    > [plain text auto-generated]
    > ----------------------------------------------------------------
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    > Attached File: http://fer3.com/arc/imgx/10N-Hc-of-Sun-vs-time.pdf
    > Attached File: http://fer3.com/arc/imgx/20N-Hc-of-Sun-vs-time.pdf
    > Attached File: http://fer3.com/arc/imgx/40N-Hc-of-Sun-vs-time.pdf
    > Attached File: http://fer3.com/arc/imgx/60N-Hc-of-Sun-vs-Time.pdf
    > Attached File: http://fer3.com/arc/imgx/80N-Hc-of-Sun-vs-time.pdf
    > View and reply to this message:
    > http://fer3.com/arc/m2.aspx/Linear-regression-other-tools-RonJones-oct-201
    > 8-g43067

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