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Longest run (nibble)

Fit to analytical expectation

Expected distribution assumes MD5 acts like a random function. The longest run of matching nibbles is the longest run of successes in 32 iid Bernoulli(1/16) 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 0.989 0.989
Std. deviation 0.508 0.508

Pearson χ² test

Samples 6,074,775,973,658,624
Reduced χ² 1.130
Degrees of freedom 13
p-value 0.327

Per-bucket detail

Bucket Observed Expected (now) Expected (end) Residual
0 770,213,472,125,641 770,213,473,212,338 43,143,988,327,398,921,283,734,558,388,424,540,160 −0.04σ
1 4,645,801,323,980,294 4,645,801,312,029,282 260,237,459,546,942,687,931,752,451,700,818,968,576 +0.18σ
2 617,068,412,521,313 617,068,423,185,061 34,565,472,785,183,526,693,054,308,602,806,796,288 −0.43σ
3 39,167,239,090,029 39,167,236,121,713 2,193,977,172,333,603,584,333,072,206,416,314,368 +0.47σ
4 2,373,089,637,832 2,373,092,618,157 132,930,263,853,445,653,755,221,868,470,599,680 −1.93σ
5 143,248,506,602 143,248,592,658 8,024,159,307,146,040,819,035,019,268,849,664 −0.23σ
6 8,634,799,277 8,634,871,374 483,687,708,315,804,001,578,566,895,534,080 −0.78σ
7 519,758,467 519,789,782 29,116,349,011,495,305,633,480,149,303,296 −1.37σ
8 31,245,868 31,243,742 1,750,137,728,324,159,119,578,837,811,200 +0.38σ
9 1,873,658 1,875,039 105,031,475,201,429,518,770,711,298,048 −1.01σ
10 112,616 112,334 6,292,458,891,074,704,389,254,938,624 +0.84σ
11 6,569 6,717 376,278,161,354,999,660,715,966,464 −1.81σ
12 434 401 22,454,852,626,045,025,552,171,008 +1.65σ
13 22 24 1,337,020,010,462,468,032,692,224 −0.38σ
14 2 1 79,413,233,237,319,619,706,880 +0.49σ
15 0 0 4,703,919,738,795,935,662,080 −0.29σ
16 0 0 277,782,025,016,212,193,280 −0.07σ
17 0 0 16,348,066,647,354,900,480 −0.02σ
18 0 0 958,422,295,699,783,680 −0.00σ
19 0 0 55,943,151,621,242,880 −0.00σ
20 0 0 3,249,056,860,078,080 −0.00σ
21 0 0 187,604,171,489,280 −0.00σ
22 0 0 10,758,893,076,480 −0.00σ
23 0 0 612,032,839,680 −0.00σ
24 0 0 34,477,178,880 −0.00σ
25 0 0 1,918,894,080 −0.00σ
26 0 0 105,185,280 −0.00σ
27 0 0 5,652,480 −0.00σ
28 0 0 295,680 −0.00σ
29 0 0 14,880 −0.00σ
30 0 0 705 −0.00σ
31 0 0 30 −0.00σ
32 0 0 1 −0.00σ