)</code></p>
<p>Increment target log probability density with <code>neg_binomial_2_log_lpmf(n | eta, phi)</code>
dropping constant additive terms.
<!-- real; neg_binomial_2_log ~; -->
</p>
</div>
<div id="stan-functions-12" class="section level3">
<h3 number="13.3.2"><span class="header-section-number">13.3.2</span> Stan Functions</h3>
<!-- real; neg_binomial_2_log_lpmf; (ints n | reals eta, reals phi); -->
<p></p>
<p><code>real</code> <strong><code>neg_binomial_2_log_lpmf</code></strong><code>(ints n | rea