of thousands of observations as in the example of persons on board the Titanic.</p>
</div>
<div class="section level3">
<h3 id="mixed-data-categorical-and-numeric-variables">Mixed data: categorical and numeric variables<a class="anchor" aria-label="anchor" href="#mixed-data-categorical-and-numeric-variables"></a>
</h3>
<p>while the <code>mtcars</code> data is quite old, it serves a good purpose here. All of the variables are coded as numeric variables, even when they should, in fact, be factor variables. In