if the j phenotypes are perfectly correlated, then the first eigenvalue equals j, and the other eigenvalues equal 0, rendering m ej = j−(j−1) = 1 (i.e., j perfectly correlated phenotypes represent only 1 unique unit of information). In practice, phenotypes show intercorrelations of variable magnitude (but not 0 or 1), so the effective number of p-values m ej will usually be smaller than j, but greater than 1. Note that m e is equal to m ej for the case that j = m, i.e., when the selection of top phenotypes covers all phenotypes.
