 code</span>
<span class="r-in"><span></span></span>
<span class="r-in"><span><span class="va">m1</span> <span class="op">&lt;-</span> <span class="fu"><a href="lmer.html">lmer</a></span><span class="op">(</span><span class="va">Reaction</span> <span class="op">~</span> <span class="va">Days</span> <span class="op">+</span> <span class="op">(</span><span class="va">Days</span> <span class="op">|</span> <span class="va">Subject</span><span class="op">)</span>, <span class="va">sleepstudy</span><span class="o