ode tries to guess <tt>N</tt> from the data.</p><pre class="codeinput">model.N = length(data.ydata);  <span class="comment">% total number of observations</span>
model.S20 = model.sigma2;      <span class="comment">% prior mean for sigma2</span>
model.N0  = 4;                 <span class="comment">% prior accuracy for sigma2</span>
</pre><p>The <tt>options</tt> structure has settings for the MCMC run. We need at least the number of simulations in <tt>nsimu</tt>. Here we also set the option <tt>updatesigma</