sured for each individual.
</p>

<ul>
<li><p> &quot;treat&quot;
is the treatment assignment (1=treated, 0=control).
</p>
</li>
<li><p> &quot;age&quot; is age in years.
</p>
</li>
<li><p> &quot;educ&quot; is education in number of years of schooling.
</p>
</li>
<li><p> &quot;race&quot; is the individual's race/ethnicity, (Black, Hispanic, or White). Note
previous versions of this dataset used indicator variables <code>black</code> and
<code>hispan</code> instead of a single race variable.
</p>
</li>
<li><p> 