ior for the different <em>intervals</em>. Week intervals start on Sundays, day intervals start on the first day found in the datetime variable. In many situations the user will be content with <code>thicken</code>’s defaults. However, you can specify the <code>start_val</code> as an offset if you would like to start the returned interval on a different day or datetime.</p>
<p>We use the emergency data set for further illustration. It contains 120,450 emergency calls in Montgomery County, PA, between 2015-