external-link">boxplot</a></span><span class="op">(</span><span class="va">cost</span> <span class="op">~</span> <span class="va">region</span>, data <span class="op">=</span> <span class="va">Appendec</span>, col <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class="st">"red"</span>, <span class="st">"blue"</span>, <span class="st">"cyan"</span><span class="op">)</span><span class="op">)</span></span></span