 aria-label="anchor" href="#arg-random-only"></a></dt>
<dd><p>complement of <code>fixed.only</code>; indicates
    whether random components only are sought. (Trying to specify
    <code>fixed.only</code> and <code>random.only</code> at the same time
    will produce an error.)</p></dd>

  <dt id="arg-correlation">correlation<a class="anchor" aria-label="anchor" href="#arg-correlation"></a></dt>
<dd><p>(logical)
    for <code>summary.merMod</code>, indicates whether the correlation matrix
    should be comp