Fig. 6: Characterizing relevant fluctuations in the danger time series of books in the corpus.

A These histograms show the number of books that have fluctuations on top of the trend (green) and those that do not (purple). The different line widths and line styles correspond to the different rescaling factors: solid thick lines for using the median of the first IMF, solid thin lines for using the 1st percentile of the first IMF, and dotted lines for no rescaling. B–D These are heatmaps that show the relationship between the period of the cutoff IMFs (as the number of words) and the book length for the various rescaling factors (shown above each plot). We can see that most of the points fall below the 45-degree line (red dashed line), indicating that the cutoff IMF period is less than the book length for the vast majority of books. The histograms for the cutoff IMF period are shown on the right side of each plot, with the 25th, 50th, and 75th percentiles shown in dotted black, solid red, and dashed black lines, respectively. The rest of the figures are similar to (B–D), but for different quantities: variance (E–G), number of IMFs (H–J; excludes the trend), and cutoff IMF order, with the first IMF counted as 1 (K–M).