Fig. 2.
The left-hand plot shows the 3D contours of the power (denoted by shade/color) as a function of 
where 
and the fourth EDTR is best. 
and 
. The right-hand plot shows power contours over the correlations where 
. Note that the power appears monotone with respect to 
and 
. The finger-shaped boundary is due to the feasible region of values for 
and 
such that 
is positive definite. The sequence of contour curves in the left-hand plot in ascending order from 
to 
corresponds to the order of the power key from 0.8 to 0.4.