g variables, <code>classid</code> and <code>schoolid</code>. We fit the simple unconditional means model in both <code>lme4</code> and <code>nlme</code> below.</p>
<div class="sourceCode" id="cb11"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span class="co"># lme4</span>
<span class="va">fm2.lmer</span> <span class="op">&lt;-</span> <span class="fu">lme4</span><span class="fu">::</span><span class="fu"><a href="https://rdrr.io/pkg/lme4/man/lmer.html">lmer</a></span><span class="op">(</spa