va">...</span><span class="op">)</span></span>
<span><span class="co"># S3 method for class 'merMod'</span></span>
<span><span class="fu"><a href="https://rdrr.io/r/stats/model.matrix.html" class="external-link">model.matrix</a></span><span class="op">(</span><span class="va">object</span>, type <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">"fixed"</span>, <span class="st">"random"</span>, <span 