de> (to provide <em>conditional</em> predicted value plots or <em>conditional</em> effect plots) and both the <code>persp()</code> method and <code>image()</code> method for <code>"lm"</code> objects, which display the same type of relationships in three-dimensions (i.e., across two conditioning covariates).</p>
<p>For example, we can use <code><a href="../reference/cplot.html">cplot()</a></code> to quickly display the predicted fuel economy of a vehicle from a model:</p>
<div class="sourceCode"><pre class=