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<p class=MsoNormal>Hi.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>I’m grid_stat’ing precip, with a fcst_thresh of ge0
and am masking against stage IV (over most of conus) file that’s projected
to the model grid and for all stage IV values ge10 (it’s a cumulative
file over about a week). When I compare model output A to stage IV, it
uses ~2500 points with one OBS mean, and when comparing model output B to stage
IV, it uses ~2600 points and finds another OBS mean. I would have thought
that this mask and fcst_thresh would use the same number of points and would compute
the same OBS mean. I.e., if there’s a model value ge0 to compare
with obs ge10 mask, the pair would be counted, and there’d be same #
pairs for both case A and case B. I would think this would be the same
for either case as I believe the model and obs files are all ge0 for this mask
(ge10 obs). I’m using the Monte Carlo error bounds with random
selection of samples which I thought might have been the issue (random sample
selection resulting in slightly different means and error bars), but it
actually results in the exact same values of mean of A etc for all reruns of
model comparison A, and the exact same values for all values of mean of B etc
for all reruns of model comparison B.<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Any thoughts?<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal>Thanks,<o:p></o:p></p>
<p class=MsoNormal>Mike<o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>______________________________________________<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>Michael
Shaw, Contractor<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>SAIC/NASA
Support Scientist<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>michael.shaw.ctr
at offutt.af.mil <o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>16WS
Environmental Characterization<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>HQ
AFWA-SAIC<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>101
Nelson Drive<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>Offutt
AFB, NE 68113-1023<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:10.5pt;font-family:Consolas'>402-232-7690
Comm * 402-272-7690 DSN * 402-294-8230 Fax<o:p></o:p></span></p>
<p class=MsoNormal><o:p> </o:p></p>
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