 interval to help diagnose changing mean</span></span></span>
<span class="r-in"><span><span class="co">#or variance structure</span></span></span>
<span class="r-in"><span><span class="va">x</span> <span class="op">&lt;-</span> <span class="fl">1</span><span class="op">:</span><span class="fl">1000</span></span></span>
<span class="r-in"><span><span class="va">y</span> <span class="op">&lt;-</span> <span class="fu"><a href="https://rdrr.io/r/stats/Normal.html" class="external-link">rnorm</a></span><span cl