/code>.
It is assumed that <code>nu</code> is in the last position of <code>param</code>.</p></td>
    </tr>
    <tr>
      <th>y</th>
      <td><p>numeric vector: response variable</p></td>
    </tr>
    <tr>
      <th>xx</th>
      <td><p>numeric matrix: the explanatory variables</p></td>
    </tr>
    <tr>
      <th>offset</th>
      <td><p>numeric vector: a vector of length equal to the number of cases</p></td>
    </tr>
    <tr>
      <th>llstart</th>
      <td><p>numeric: current log-likelihood value<