[Met_help] [rt.rap.ucar.edu #82250] History for series-analysis paired option

[John Halley Gotway via RT]

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  Initial Request
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Hello,

I am using MET6.0 series-analysis to produce 2m temperature verification.
I found that some areas have no data (see attached figure).  I am using the
"paired" option because I though that this means even if a few dates have
some missing data, it won't block everything out for that region.  Am I
misunderstanding the paired functionality?


Thanks,
Shannon
-- 
Shannon Rees
UCAR Visiting Scientist
Geophysical Fluid Dynamics Lab
Princeton University Forrestal Campus
201 Forrestal Rd Princeton, NJ
609-452-5384


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  Complete Ticket History
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Subject: series-analysis paired option
From: John Halley Gotway
Time: Wed Oct 04 19:57:43 2017

Shannon,

Yes, the -paired option means something different.  When you run
series_analysis, you pass to it a list of forecast files and a
observations
files.  The -paired option means that the first forecast file's data
matches the first observation file's data... the 2nd matches the
2nd... and
so on.  Series-Analysis has logic to search through all input files
looking
for matching data.  But the -paired option simplifies that logic.

However, I believe the vld_thresh config file option applies to the
situation you describe:

//
// Ratio of valid matched pairs to compute statistics for a grid point
//
vld_thresh = 1.0;


Suppose your series is of length 10.  Setting vld_thresh to 0.5 would
require that only 5 of the 10 pairs for each grid point contain valid
data
in order for stats to be computed.  The default value of 1.0 requires
that
all series values must be valid for stats to be computed.

If you set vld_thresh less than 1.0, I'd strongly recommend writing
out the
"TOTAL" statistic.  That'll tell you how many valid values occurred at
each
grid point.

Thanks,
John

On Wed, Oct 4, 2017 at 3:54 PM, Shannon Rees - NOAA Affiliate via RT <
met_help at ucar.edu> wrote:

>
> Wed Oct 04 15:54:19 2017: Request 82250 was acted upon.
> Transaction: Ticket created by shannon.rees at noaa.gov
>        Queue: met_help
>      Subject: series-analysis paired option
>        Owner: Nobody
>   Requestors: shannon.rees at noaa.gov
>       Status: new
>  Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=82250 >
>
>
> Hello,
>
> I am using MET6.0 series-analysis to produce 2m temperature
verification.
> I found that some areas have no data (see attached figure).  I am
using the
> "paired" option because I though that this means even if a few dates
have
> some missing data, it won't block everything out for that region.
Am I
> misunderstanding the paired functionality?
>
>
> Thanks,
> Shannon
> --
> Shannon Rees
> UCAR Visiting Scientist
> Geophysical Fluid Dynamics Lab
> Princeton University Forrestal Campus
> 201 Forrestal Rd Princeton, NJ
> 609-452-5384
>
>

------------------------------------------------
Subject: series-analysis paired option
From: Shannon Rees - NOAA Affiliate
Time: Thu Oct 05 12:19:48 2017

Hi John,

This worked for me.  Thanks for the clarification.  I see now that
only one
case had missing data which was masking out most of the analysis.  You
can
close the ticket.

Best,
Shannon

On Wed, Oct 4, 2017 at 9:57 PM, John Halley Gotway via RT
<met_help at ucar.edu
> wrote:

> Shannon,
>
> Yes, the -paired option means something different.  When you run
> series_analysis, you pass to it a list of forecast files and a
observations
> files.  The -paired option means that the first forecast file's data
> matches the first observation file's data... the 2nd matches the
2nd... and
> so on.  Series-Analysis has logic to search through all input files
looking
> for matching data.  But the -paired option simplifies that logic.
>
> However, I believe the vld_thresh config file option applies to the
> situation you describe:
>
> //
> // Ratio of valid matched pairs to compute statistics for a grid
point
> //
> vld_thresh = 1.0;
>
>
> Suppose your series is of length 10.  Setting vld_thresh to 0.5
would
> require that only 5 of the 10 pairs for each grid point contain
valid data
> in order for stats to be computed.  The default value of 1.0
requires that
> all series values must be valid for stats to be computed.
>
> If you set vld_thresh less than 1.0, I'd strongly recommend writing
out the
> "TOTAL" statistic.  That'll tell you how many valid values occurred
at each
> grid point.
>
> Thanks,
> John
>
> On Wed, Oct 4, 2017 at 3:54 PM, Shannon Rees - NOAA Affiliate via RT
<
> met_help at ucar.edu> wrote:
>
> >
> > Wed Oct 04 15:54:19 2017: Request 82250 was acted upon.
> > Transaction: Ticket created by shannon.rees at noaa.gov
> >        Queue: met_help
> >      Subject: series-analysis paired option
> >        Owner: Nobody
> >   Requestors: shannon.rees at noaa.gov
> >       Status: new
> >  Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=82250 >
> >
> >
> > Hello,
> >
> > I am using MET6.0 series-analysis to produce 2m temperature
verification.
> > I found that some areas have no data (see attached figure).  I am
using
> the
> > "paired" option because I though that this means even if a few
dates have
> > some missing data, it won't block everything out for that region.
Am I
> > misunderstanding the paired functionality?
> >
> >
> > Thanks,
> > Shannon
> > --
> > Shannon Rees
> > UCAR Visiting Scientist
> > Geophysical Fluid Dynamics Lab
> > Princeton University Forrestal Campus
> > 201 Forrestal Rd Princeton, NJ
> > 609-452-5384
> >
> >
>
>


--
Shannon Rees
UCAR Visiting Scientist
Geophysical Fluid Dynamics Lab
Princeton University Forrestal Campus
201 Forrestal Rd Princeton, NJ
609-452-5384 <(609)%20452-5384>

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