 \phi)\)</span>.</p>
<p>There are two problems that still arise, though. The first is that if
the posterior mass for <span class="math inline">\(\phi\)</span> is near one of the boundaries, the
logit-transformed parameter will have to sweep out long paths and
thus can dominate the U-turn condition imposed by the no-U-turn
sampler (NUTS). The second issue is that the inverse transform from
the unconstrained space to the constrained space can underflow to 0 or
overflow to 1, even when the unconstrained parame