 for \(a\) parameters to be estimated.
If <code>est.a="2PL"</code>, then all item loadings will be estimated and the
variances are set to one (and therefore <code>est.corr=TRUE</code>).</p></dd>

  <dt>est.c</dt>
<dd><p>An integer vector for \(c\) parameters to be estimated</p></dd>

  <dt>est.d</dt>
<dd><p>An integer vector for \(d\) parameters to be estimated</p></dd>

  <dt>est.mu.i</dt>
<dd><p>An integer vector for \(\mu_i\) parameters to be estimated</p></dd>

  <dt>b.init</dt>
<dd><p>Initial \(b\) coe