ss="fu">colnames</span>(X) <span class="ot">&lt;-</span> <span class="fu">paste0</span>(<span class="st">&quot;X&quot;</span>, <span class="dv">1</span><span class="sc">:</span>p)</span>
<span id="cb1-7"><a href="#cb1-7" aria-hidden="true" tabindex="-1"></a>y <span class="ot">&lt;-</span> <span class="dv">1</span> <span class="sc">+</span> <span class="fl">0.4</span> <span class="sc">*</span> <span class="fu">rowSums</span>(X[, <span class="fu">c</span>(<span class="dv">5</span>, <span class="dv">10</span>,