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Longest run (byte)

Fit to analytical expectation

Expected distribution assumes MD5 acts like a random function. The longest run of matching bytes is the longest run of successes in 16 iid Bernoulli(1/256) trials.

Expected (now) scales that analytical distribution to the hashes computed so far; Expected (end) scales it to the full 2128 keyspace. Residual is the Pearson residual (Observed − Expected) / √Expected in units of σ. A p-value near 1 means the observed distribution is consistent with random; near 0 means it is statistically surprising.

Distribution moments

Observed Expected
Mean 0.061 0.061
Std. deviation 0.240 0.240

Pearson χ² test

Samples 6,074,926,297,513,984
Reduced χ² 0.735
Degrees of freedom 6
p-value 0.622

Per-bucket detail

Bucket Observed Expected (now) Expected (end) Residual
0 5,706,166,713,760,024 5,706,166,703,950,157 319,626,579,315,078,477,702,860,203,058,987,532,288 +0.13σ
1 367,374,324,051,975 367,374,332,120,950 20,578,193,241,829,676,409,493,019,032,534,646,784 −0.42σ
2 1,380,208,813,197 1,380,210,518,097 77,311,440,327,981,424,594,731,781,555,486,720 −1.45σ
3 5,032,570,460 5,032,603,505 281,897,450,027,020,305,594,801,276,846,080 −0.47σ
4 18,252,166 18,255,212 1,022,551,769,974,266,797,027,644,932,096 −0.71σ
5 65,908 65,827 3,687,270,973,483,576,287,213,649,920 +0.31σ
6 252 236 13,203,902,706,800,148,453,785,600 +1.06σ
7 2 1 46,892,199,896,121,983,631,360 +1.27σ
8 0 0 164,869,745,483,616,092,160 −0.05σ
9 0 0 572,526,699,699,240,960 −0.00σ
10 0 0 1,957,152,172,277,760 −0.00σ
11 0 0 6,554,187,202,560 −0.00σ
12 0 0 21,340,815,360 −0.00σ
13 0 0 66,716,160 −0.00σ
14 0 0 195,585 −0.00σ
15 0 0 510 −0.00σ
16 0 0 1 −0.00σ