d. Argument <code>pi</code> can be used to denote the proportion of individuals falling into the first of the two groups that is created by the dichotomization (hence, <code>1-pi</code> falls into the second group). If <code>pi</code> is not specified, the function assumes <code>pi=0.5</code>, which corresponds to dichotomization at the median. This function is simply the inverse of <code>transf.rpbtorbis</code>.</p></li>
<li><p><code>transf.rtod</code>: transformation of Pearson product-moment correlations