 regress(fnctl = "mean", formula = atrophy ~ age, data = mri)</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> </span>
<span class="r-out co"><span class="r-pr">#&gt;</span> Residuals:</span>
<span class="r-out co"><span class="r-pr">#&gt;</span>     Min      1Q  Median      3Q     Max </span>
<span class="r-out co"><span class="r-pr">#&gt;</span> -36.870  -8.589  -0.870   7.666  51.203 </span>
<span class="r-out co"><span class="r-pr">#&gt;</span> </span>
<span class="r-out co"><span class="r-