With this menu, you can compute the following average values:
Overall: Computes and displays the overall average.
Within groups: This item is enabled only if at least one group is defined. For each group, an arithmetic average is computed for all valid pairwise comparisons and the results are displayed in the Distance Matrix Explorer. All incalculable within-group averages are shown with an n/c in red.
Between Groups: This item is enabled only if at least two groups of taxa are defined. For each between-group average, an arithmetic average is computed for all valid inter-group pairwise comparisons and results are displayed in the Distance Matrix Explorer. All incalculable within-group averages are shown with an n/c in red.
Net Between Groups: This item is enabled only if at least two groups of taxa are defined. It computes net average distances between groups of taxa. This value is given by
dA = dXY (dX + dY)/2
where dXY is the average distance between groups X and Y, and dX and dY are the mean within-group distances. You must have at least two groups of taxa with a minimum of two taxa each for this option to work. All incalculable within-group averages are shown with a red n/c.