hich contains the upper asymptote parameters for each item. In the case of polytomous items, the value must be 1.</p></td>
    </tr>
    <tr>
      <th>theta_start</th>
      <td><p>A vector which contains a starting value for each person. If NULL is submitted, the starting values are set automatically. If a scalar is submitted, this start value is used for each person.</p></td>
    </tr>
    <tr>
      <th>mu</th>
      <td><p>A numeric vector of location parameters for each person in case of MAP estimatio