code>NA</code> values in the columns to be summarized will generally
result in an error. If <code>TRUE</code>, <code>NA</code> values will be removed in the calculation of intervals so long
as <code>.interval</code> is <code>"mhd"</code>; other methods do not currently support <code>na.rm</code>. Be cautious in applying
this parameter: in general, it is unclear what a joint interval should be when any of the values
are missing!</p></dd>


<dt id="arg--interval">.interval<a class="anchor" aria-label="anchor"