<p>We have two tags that seem closely related:</p>
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<li><p><a href="https://stats.stackexchange.com/questions/tagged/hauck-donner-effect" class="post-tag" title="show questions tagged &#39;hauck-donner-effect&#39;" rel="tag">hauck-donner-effect</a> (69 threads) Excerpt:</p>
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<p>Also called &quot;perfect separation&quot;. In logistic regression, if all 1 &amp; 0 outcomes lie on different sides of some value for a variable, the coefficient estimate for that variable will tend towards infinity.</p>
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<li><p><a href="https://stats.stackexchange.com/questions/tagged/separability" class="post-tag" title="show questions tagged &#39;separability&#39;" rel="tag">separability</a> (37 threads) Excerpt:</p>
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<p>separability is when two classes in the data can be completely separated, i.e. by some (hyper)plane, such that for instance a logistic regression, svm or discriminant analysis can give perfect predictions on the training data. See the wikipedia article on Separation (statistics)</p>
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<p>There are 12 threads that have both tags.</p>
<p>I'm wondering if the distinction between them, and when one or the other should be used, can be made clearer.  Alternatively, should one be made a synonym of the other?  (Which?)</p>
