ther to create a longer dataframe. Generally, this is a more flexible format for analysis than the wide data format. In our math/ela example, it allows us to, for example, easily average the math and ela test scores together (filtering for group, year, etc).</p>
<p>In the example here we will add a new column, <code class="docutils literal notranslate"><span class="pre">test</span></code>, which will have the value of “ela” or “math”. This column will let us know whether that row reports a math test