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<p>to an <a href="page.php?w=White_House_Office">organization</a> instead of a <a href="page.php?w=White_House">location</a>.</p>

<p><big>Formal evaluation</big></p>
<p>To evaluate the quality of an NER system's output, several measures have been defined. The usual measures are called <a href="page.php?w=Precision_and_recall">precision, recall</a>, and <a href="page.php?w=F1_score">F1 score</a>. However, several issues remain in just how to calculate those values.</p>

<p>These statistical measures work reasonably well for the obvious cases of finding or</p><p>
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