class="r-in"><span><span class="co"># We use the same dataset for a single subject with two codes, for</span></span></span>
<span class="r-in"><span><span class="co"># complicated and uncomplicated diabetes:</span></span></span>
<span class="r-in"><span><span class="va">x3</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/r/base/data.frame.html" class="external-link">data.frame</a></span><span class="op">(</span></span></span>
<span class="r-in"><span>  id <span class="op">=</sp