[teqc] about "missed obs" on TEQC report

Lou Estey lou at unavco.org
Thu Jul 15 10:41:47 MDT 2010


Dear Simón,

> I would like to know how the field “Missed obs” in the TEQC+qc report is
> computed. In the attached TEQC+qc report it does not happen that:
>
> Possible obs = complete obs + missed obs + deleted obs
>
> as one would probably expect. I have been able to understand how the
> fields “Possible obs”, “complete obs” and “deleted obs” from the TEQC-qc
> report are computed, but this is not the case for “missed obs”. Could
> you please tell me how is “Missed obs” exactly computed?

No, "missed obs" is not that at all.  I will admit that the current
labeling in the qc summary is pretty confusing, as in your attached
file shows:

Possible obs >  10.0 deg:  20244
Complete obs >  10.0 deg:  14473
   Missed obs >  10.0 deg:   5072
  Deleted obs >  10.0 deg:    347

"Missed obs" as added in 7 Mar 2009 (see
http://facility.unavco.org/software/teqc/log.html ) and is
related to the discrepancy lines '-dn' and '+dn':

-dn|  ++++++++  + ++  11211 + ++++++ ++++  +122243433444444465556765588888  |-dn
+dn| 1 51 3       525713412 4 5 2 1   21411123344444445554468688777688888881|+dn

See all those '+' values on the '-dn' line?  That's telling you that
there is good data below 10 degrees (which is the default value for
the cutoff mask for the qc).  The "missed obs" count is the actual
number of obs below the cutoff mask, i.e. you've "missed" using them
in the qc if you keep the cutoff mask as is. If you lower the mask value
(using the '-set_mask #' option), then the '+'s on the '-dn' line
should become reduced in number and as should the "missed obs" count.

What you where thinking of is ... "totally absent obs"?

absent obs = possible obs - complete obs - deleted obs

You can compute this yourself using the values provided, where
this is, like the rest, dependent on the cutoff mask angle.

cheers,
--lou

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Louis H. Estey, Ph.D.              office:  [+001] 303-381-7456
UNAVCO, 6350 Nautilus Drive           FAX:  [+001] 303-381-7451
Boulder, CO  80301-5554            e-mail:  lou  unavco.org
    WWW:  http://www.unavco.org   http://jules.unavco.org

"If the universe is the answer, what is the question?"
                                                -- Leon Lederman
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


More information about the teqc mailing list