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Apparent inability of human observers to understand and mimic randomness has occupied researchers for a long time. According to a recent report, the special status of streaks in randomness perception reflects sensitivity to subtle statistical properties of pattern structure. In PNAS, Sun et al.(1) have highlighted one such property, namely, waiting time, as possibly responsible for the biases in randomness perception. Although the probability of any outcome in a truly random sequence is equal, inherent structural differences between patterns affect the probabilities of their occurrence at different points of the tossing process. Specifically, patterns that possess the maximum degree of selfoverlap (eg, HHHH) are easily disrupted by individual tosses unlike nonoverlapping patterns (eg, HHHT) and, as such, have the longest waiting time (time of first occurrence) because they tend to cluster together, accounting for the …