or</p>
</dd>
<dt><code>frequency</code></dt><dd><p>a numeric vector</p>
</dd>
<dt><code>gp</code></dt><dd><p>a factor with levels <code>fd</code> <code>fs</code> <code>md</code> <code>ms</code></p>
</dd>
<dt><code>par</code></dt><dd><p>a factor with levels <code>Father</code> <code>Mother</code></p>
</dd>
<dt><code>chl</code></dt><dd><p>a factor with levels <code>Daughter</code> <code>Son</code></p>
</dd>
</dl>



<h3>Details</h3>

<p>The variables <code>gp</code>, <code>par</code> and <code>chl</code> are 