an></span>
<span></span>
<span><span class="co"># S3 method for class 'pibblefit'</span></span>
<span><span class="fu">r2</span><span class="op">(</span><span class="va">m</span>, covariates <span class="op">=</span> <span class="cn">NULL</span>, <span class="va">...</span><span class="op">)</span></span>
<span></span>
<span><span class="co"># S3 method for class 'bassetfit'</span></span>
<span><span class="fu">r2</span><span class="op">(</span><span class="va">m</span>, covariates <span class="op">=</span>