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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 13,403,944,390,754,304
Reduced χ² 2.111
Degrees of freedom 6
p-value 0.049

Per-bucket detail

Bucket Observed Expected (now) Expected (end) Residual
0 12,590,299,515,999,266 12,590,299,443,702,118 319,626,579,315,078,477,702,860,203,058,987,532,288 +0.64σ
1 810,588,383,357,513 810,588,454,440,154 20,578,193,241,829,676,409,493,019,032,534,646,784 −2.50σ
2 3,045,346,844,880 3,045,348,062,852 77,311,440,327,981,424,594,731,781,555,486,720 −0.70σ
3 11,104,126,232 11,104,124,431 281,897,450,027,020,305,594,801,276,846,080 +0.02σ
4 40,279,866 40,278,981 1,022,551,769,974,266,797,027,644,932,096 +0.14σ
5 145,996 145,244 3,687,270,973,483,576,287,213,649,920 +1.97σ
6 547 520 13,203,902,706,800,148,453,785,600 +1.18σ
7 4 2 46,892,199,896,121,983,631,360 +1.58σ
8 0 0 164,869,745,483,616,092,160 −0.08σ
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