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Fig. 4. Intensity reduction is more dissimilar from the average intensity reduction
when plotted against time, than against distance. Equal dissimilarity would
result in a slope of 1. Dissimilarity from average intensity reduction over
time (x-axis) is plotted against dissimilarity from average intensity
reduction over distance (y-axis), and the units of both are %
dissimilarity from slope of the average linear regression line of reduction
against time and distance, respectively.