logit-transformed
to <span class="math inline">\((-\infty,\infty)\)</span>. The boundaries at 0 and 1 are pushed out to
<span class="math inline">\(-\infty\)</span> and <span class="math inline">\(\infty\)</span> respectively. The Jacobian adjustment that
Stan automatically applies ensures the unconstrained density is
proper. The adjustment for the particular case of <span class="math inline">\((0,1)\)</span> is <span class="math inline">\(\log \operatorname{logit}^{-1}(\phi) + \log \operatorname{logit}(1 -