Integrated periodograms for the run volume data. The Fourier transform of
the time series variable is used to generate an equivalent representation
as a sequence of sinusoidal terms. This procedure decomposes the total
variance of the data into contributions as a function of frequency.The horizontal axis
shows frequency and the vertical axis shows the cumulative sum of the squared amplitudes, normalized to a 0-1 scale. Models yielding plots that fall within the 95% Kolmogorov Smirnov confidence bounds are likely to be genuinely random or "white noise"
processes; these indicate the best models. The 1995 test data are shown in the first
plot. Subsequent plots show the residuals of increasingly accurate forecast models