are used for correcting estimation bias of the
stand-level variables caused by the lack of detection of trees due to
occlusion.</p>
<p>A list with three elements is generated by the
<code>distance.sampling</code> function. The data frame
<strong><code>tree</code></strong> represents the detection
probabilities for each tree of all plots according to the four different
detection functions. The columns <code>P.hn</code> and
<code>P.hn.cov</code> show the detection probabilities calculated by the
half normal f