the survivors and non-survivors. With two categorical variables, each with two levels, there are four distinct model values.</p>
<p><strong>Categorical &amp; quantitative</strong></p>
<p>This example shows (full-grown) child’s height as a function of the child’s sex and his or her mother’s height.</p>
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<div class="sourceCode cell-code" id="cb2"><pre class="sourceCode r code-with-copy"><code class="sourceCode r"><span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><s