a-level="1.4.4" data-path="introduction.html"><a href="introduction.html#sampling-from-a-population"><i class="fa fa-check"></i><b>1.4.4</b> Sampling from a population</a></li>
</ul></li>
<li class="chapter" data-level="1.5" data-path="introduction.html"><a href="introduction.html#causality-and-statistics"><i class="fa fa-check"></i><b>1.5</b> Causality and statistics</a></li>
<li class="chapter" data-level="1.6" data-path="introduction.html"><a href="introduction.html#learning-objectives"><i class="fa fa-c