<p>After the brief discussion in the comments above, I wrote a tag wiki excerpt for <a href="https://stats.stackexchange.com/questions/tagged/correlation-matrix" class="post-tag" title="show questions tagged &#39;correlation-matrix&#39;" rel="tag">correlation-matrix</a> and tagged a dozen of old threads with it, where it seemed the most appropriate. So it seems the tag is here to stay.</p>
