John Carmichael asked:

> Is the average EOT correction over the course of the entire year equal to
> about seven or eight minutes? from (16+15)/2/2=7.75 min.. As 16 minutes is
> about the extreme correction on Nov. 1st. and 15 minutes is the other
> extreme corroction in mid Febuary.  Does anybody know the exact average?  


I reported on several different error statistics for EoT in a paper I gave
at the Seattle 1998 NASS shindig.  And I've promised Fred Sawyer that a
write-up of my talk will eventually be submitted to _The Compendium_.
Oh, for a few more hours in the day....


Mean error:  0.0 minutes
(The average error over one year, taking into account the sign of EoT.)

Mean absolute error:  7.2 minutes
(The average error when taking all EoT errors to be nonnegative.)

Root-mean-square error:  8.7 minutes
(The square root of the average of the squares of all EoT errors.)


~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~  ~ 
  Mark Gingrich      [EMAIL PROTECTED]      San Leandro, California

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