R-Value and Free R-Value

[Gerard Pujadas]

        Hi to all, my name is Gerard Pujadas and I wonder which is the
difference between this two concepts which often are in the same PDB file:
R VALUE and FREE R VALUE. Which may be used as a measure of the refinement
quality of a protein X-ray structure. Please reply soon.

        Thanks in advances. Yours sincerelly.

        Gerard.

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* Gerard Pujadas                                                          *
* Biotecnologia Computacional                                             *
* Dept. Bioquimica i Biotecnologia         e-mail: pujadas at quimica.urv.es *
* Univ. Rovira i Virgili                   phone: 34 77 559565            *
* Pla=E7a Imperial Tarraco 1                 fax: 34 77 559597              =
*
* 43005 Tarragona (CATALONIA) Europe.                                     *
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