[Met_help] [rt.rap.ucar.edu #69859] History for Query Reg The Bias

[John Halley Gotway via RT]

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  Initial Request
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Hi John, 
there are two o/p CNT and CTS (statistcs). 
In CTS type, U have the O/p as FBIAS (frequency Bias) and in the other one is CNT (contoius statistics), U have the O/P MULTIPLICATIVE bias. 

Kindly explain the difference b/w the two. 

I know freq bias =(a+c)/(a+B) (freq of FCST/freq of obs). 

The linear bias or the Mean Error is = 1/n sum ((Fi-Oi) ) where i vaires from 1=N. 

Pls explain the difference b/w Mutiplicative bias and freq bias and linear bias???

geeta 		 	   		  

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  Complete Ticket History
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Subject: Query Reg The Bias
From: Julie Prestopnik
Time: Mon Nov 24 10:04:54 2014

Hello.  John is out of the office this week, but will return next
week.
Unfortunately, I am unable to answer your question.  John will get
back
with you as soon as he can.

Thanks,
Julie

On Sun, Nov 23, 2014 at 11:48 PM, Geeta Geeta via RT
<met_help at ucar.edu>
wrote:

>
> Sun Nov 23 23:48:41 2014: Request 69859 was acted upon.
> Transaction: Ticket created by geeta124 at hotmail.com
>        Queue: met_help
>      Subject: Query Reg The Bias
>        Owner: Nobody
>   Requestors: geeta124 at hotmail.com
>       Status: new
>  Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=69859 >
>
>
>
> Hi John,
> there are two o/p CNT and CTS (statistcs).
> In CTS type, U have the O/p as FBIAS (frequency Bias) and in the
other one
> is CNT (contoius statistics), U have the O/P MULTIPLICATIVE bias.
>
> Kindly explain the difference b/w the two.
>
> I know freq bias =(a+c)/(a+B) (freq of FCST/freq of obs).
>
> The linear bias or the Mean Error is = 1/n sum ((Fi-Oi) ) where i
vaires
> from 1=N.
>
> Pls explain the difference b/w Mutiplicative bias and freq bias and
linear
> bias???
>
> geeta
>



--
Julie Prestopnik
National Center for Atmospheric Research
Research Applications Laboratory
Phone: 303.497.8399
Email: jpresto at ucar.edu

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Subject: Query Reg The Bias
From: John Halley Gotway
Time: Mon Dec 01 13:42:17 2014

Geeta,

I see that you understand the categorical frequency bias and
continuous
mean error (linear bias), and you're wondering how the multiplicative
bias
is defined.

The equations for all of these statistics can be found in Appendix C
of the
MET User's Guide:

http://www.dtcenter.org/met/users/docs/users_guide/MET_Users_Guide_v5.0.pdf

The multiplicative bias is just the average forecast value divided by
the
average observed value.  A perfect score is 1.  Values over 1 indicate
larger forecast values while values less than indicate larger
observation
values.

John



On Mon, Dec 1, 2014 at 1:30 PM, Julie Prestopnik via RT
<met_help at ucar.edu>
wrote:

>
> Mon Dec 01 13:30:37 2014: Request 69859 was acted upon.
> Transaction: Given to johnhg by jpresto
>        Queue: met_help
>      Subject: Query Reg The Bias
>        Owner: johnhg
>   Requestors: geeta124 at hotmail.com
>       Status: open
>  Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=69859 >
>
>
> This transaction appears to have no content
>

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