span class="special">);</span>
</pre>
<p>
          Returns the smallest number of trials we must conduct to be 95% sure of
          seeing 10 failures that occur with frequency one half.
        </p>
<p>
          <a class="link" href="../../stat_tut/weg/neg_binom_eg/neg_binom_size_eg.html" title="Estimating Sample Sizes for the Negative Binomial.">Worked
          Example.</a>
        </p>
<p>
          This function uses numeric inversion of the negative binomial distribution
          to obtain the res