<p>In my field of oceanography, objective analysis (<strong>OA</strong>) is often taken as a synonym of optimal interpolation (<strong>OI</strong>). (e.g. <a href="https://books.google.com/books?hl=en&amp;lr=&amp;id=59fEAgAAQBAJ&amp;oi=fnd&amp;pg=PP1&amp;dq=emery%20thomson&amp;ots=Go9-M8l-mf&amp;sig=RveHg386O6cEiW7jprmvt4G9WBg#v=onepage&amp;q=emery%20thomson&amp;f=false" rel="nofollow">Emery &amp; Thomson</a>, Section 4.2; and <a href="http://marine.rutgers.edu/dmcs/ms615/JW-lecture-OI.pdf" rel="nofollow">in many lectures</a>). </p>

<p>The same method is also referred to as objective mapping or Gauss-Markov smoothing. In this case OA is a least squared interpolation where the estimate is unbiased and the expected error is a minimum in the least squares sense.  </p>

<p>In many other cases, objective analysis is taken to be a specific type of optimal interpolation. A good example is the group from <a href="http://modb.oce.ulg.ac.be/wiki/upload/diva_intro.pdf" rel="nofollow">University of Liege</a>. In this case OI includes other methods like <a href="http://en.wikipedia.org/wiki/Kriging" rel="nofollow">kriging</a>, <a href="http://en.wikipedia.org/wiki/Barnes_interpolation" rel="nofollow">successive corrections</a> or the Cressman method. </p>

<p>In my case, I tend to follow the nomenclature and suggestions by <a href="http://www.academia.edu/download/31042285/10.1.1.47.2607.pdf" rel="nofollow">Ide et al. (1997)</a>. </p>

CC BY-SA 3.0
2015-04-24T02:20:47.480Z
This is great - thanks aretxabaleta. I'm having trouble with the above link for Ide; I believe the paper's title is: "Unied Notation for Data Assimilation:
Operational, Sequential and Variational". And another link is: http://twister.ou.edu/OBAN2010/IdeEtal_1997_Notation.pdf
user4624937
CC BY-SA 3.0
2015-04-24T11:49:16.737Z
Ide, K., Courtier, P., Ghil, M., & Lorenc, A. C. (1997). Unified notation for data assimilation: operational, sequential and variational. J. Met. Soc. Japan. Special Issue in Meteorology and Oceanography: Theory and Practice, 75(1B), 181-189.
arkaia
CC BY-SA 3.0
2015-04-24T11:50:21.673Z
http://twister.caps.ou.edu/OBAN2004/IdeEtal_1997_Notation.pdf  ftp://128.149.132.117/data3/ATN_output/%2Btemp/%2Bseaice/IdeEtal_1997_Notation.pdf
arkaia
CC BY-SA 3.0
2015-04-24T01:02:08.840Z
2015-04-24T01:27:55.667Z
2015-04-24T01:27:55.667Z
arkaia
<p>I've found that there may possibly be many meanings of "objectively analyzed" and "objective analysis" in modeling and data assimilation. What are some of the accepted meanings?</p>

<models><atmosphere-modelling>
Meaning of "Objectively analyzed"
user4624937
# Meaning of "Objectively analyzed"

(Asked by: username_0 on 2015-04-23)

I've found that there may possibly be many meanings of "objectively analyzed" and "objective analysis" in modeling and data assimilation. What are some of the accepted meanings?

**Tags:** models, atmosphere-modelling


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## 1 answers

### Answer by username_1 on 2015-04-24. Score: 4 | Accepted answer

In my field of oceanography, objective analysis (**OA**) is often taken as a synonym of optimal interpolation (**OI**). (e.g. [Emery & Thomson](https://books.google.com/books?hl=en&lr=&id=59fEAgAAQBAJ&oi=fnd&pg=PP1&dq=emery%20thomson&ots=Go9-M8l-mf&sig=RveHg386O6cEiW7jprmvt4G9WBg#v=onepage&q=emery%20thomson&f=false), Section 4.2; and [in many lectures](http://marine.rutgers.edu/dmcs/ms615/JW-lecture-OI.pdf)).

The same method is also referred to as objective mapping or Gauss-Markov smoothing. In this case OA is a least squared interpolation where the estimate is unbiased and the expected error is a minimum in the least squares sense.

In many other cases, objective analysis is taken to be a specific type of optimal interpolation. A good example is the group from [University of Liege](http://modb.oce.ulg.ac.be/wiki/upload/diva_intro.pdf). In this case OI includes other methods like [kriging](http://en.wikipedia.org/wiki/Kriging), [successive corrections](http://en.wikipedia.org/wiki/Barnes_interpolation) or the Cressman method.

In my case, I tend to follow the nomenclature and suggestions by [Ide et al. (1997)](http://www.academia.edu/download/31042285/10.1.1.47.2607.pdf).

> **Comments:**
> **username_0**: This is great - thanks aretxabaleta. I'm having trouble with the above link for Ide; I believe the paper's title is: "Unied Notation for Data Assimilation: Operational, Sequential and Variational". And another link is: http://twister.ou.edu/OBAN2010/IdeEtal_1997_Notation.pdf  
> **username_1**: Ide, K., Courtier, P., Ghil, M., & Lorenc, A. C. (1997). Unified notation for data assimilation: operational, sequential and variational. J. Met. Soc. Japan. Special Issue in Meteorology and Oceanography: Theory and Practice, 75(1B), 181-189.  
> **username_1**: http://twister.caps.ou.edu/OBAN2004/IdeEtal_1997_Notation.pdf  ftp://128.149.132.117/data3/ATN_output/%2Btemp/%2Bseaice/IdeEtal_1997_Notation.pdf  

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