shapes of the frequency boxes,
with 2 options:</p><ol><li><p><code>"no"</code>: rectangular frequency boxes, not scaled (default);</p></li>
<li><p><code>"sq"</code>: frequency boxes are squares (scaled relative to N).</p></li>
</ol></dd>


<dt>scale</dt>
<dd><p>Scale probabilities and corresponding area dimensions either by
exact probability or by (rounded or non-rounded) frequency, with 2 options:</p><ol><li><p><code>"p"</code>: scale main area dimensions by exact probability (default);</p></li>
<li><p><co