Figure 4. Extent to which the cumulative distribution for UEE spikes follows a power-law, for the subset having durations greater than 1 second (upper panel) and less than 1 second (lower panel).

For durations more than 1 second, there is strong evidence for a power-law (p-value is 0.912). For durations less than 1 second, a power-law can be rejected. Black line shows best-fit power-law.