The wavelet coefficients at each scale have a certain statistical distribution, which can be approximated as a normalized histogram. When this is done for the energy map, with the energy scale distributed logarithmically, the result is shown on Fig. 26. It can be shown that the mean magnitude at each duration reproduces the mean power spectrum in log-log coordinates. Therefore, this particular presentation of the probability density function shows graphically the scale-dependent scatter around the mean energy spectrum.
