span class="r-in"><span>                    center_group <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/list.html" class="external-link">list</a></span><span class="op">(</span><span class="st">"Subject"</span> <span class="op">=</span> <span class="op">~</span><span class="va">Days</span><span class="op">)</span><span class="op">)</span></span></span>
<span class="r-in"><span></span></span>
<span class="r-in"><span><span class="co">#Run three level model with random slope and in