io/r/stats/lm.html" class="external-link">lm</a></span><span class="op">(</span><span class="va">y</span> <span class="op">~</span> <span class="va">x</span><span class="op">)</span><span class="op">)</span><span class="op">[</span><span class="fl">1</span><span class="op">]</span>,</span></span>
<span class="r-in"><span>       xlab <span class="op">=</span> <span class="st">"Days of sleep deprivation"</span>,</span></span>
<span class="r-in"><span>       ylab <span class="op">=</span> <span class="st">"Ave