used if <code>bootstrap = TRUE</code>
and <code>sample_splitting = FALSE</code>); defaults to 1000.</p></dd>


<dt>boot_interval_type</dt>
<dd><p>the type of bootstrap interval (one of <code>"norm"</code>,
<code>"basic"</code>, <code>"stud"</code>, <code>"perc"</code>, or <code>"bca"</code>, as in
<code>boot.ci</code>) if requested. Defaults to <code>"perc"</code>.</p></dd>


<dt>clustered</dt>
<dd><p>should the bootstrap resamples be performed on clusters
rather than individual observations? Defaults to <c