 the log probability accumulator may only be used within the transformed parameters block.</p>
<p>Functions whose names end in <code>_rng</code> assume access to the random number generator and may only be used within the generated quantities block, transformed data block, and within user-defined functions ending in <code>_rng</code>.</p>
<p>Functions whose names end in <code>_lpdf</code> and <code>_lpmf</code> can be used anywhere. However, <code>_lupdf</code> and <code>_lupmf</code> functions can only be 