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Match count (nibble)

Fit to analytical expectation

Expected distribution assumes MD5 acts like a random function. The matching-nibble count is Binomial(32, 1/16): each of the 32 output nibbles matches its input nibble independently with probability 1/16.

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 2.000 2.000
Std. deviation 1.369 1.369

Pearson χ² test

Samples 13,404,004,520,296,448
Reduced χ² 0.689
Degrees of freedom 19
p-value 0.834

Per-bucket detail

Bucket Observed Expected (now) Expected (end) Residual
0 1,699,477,437,065,455 1,699,477,465,720,213 43,143,988,327,398,911,839,001,592,649,134,112,768 −0.70σ
1 3,625,551,959,286,048 3,625,551,926,869,770 92,040,508,431,783,893,168,652,104,264,117,649,408 +0.54σ
2 3,746,403,652,589,102 3,746,403,657,765,380 95,108,525,379,508,778,125,135,623,301,109,907,456 −0.08σ
3 2,497,602,443,658,808 2,497,602,438,510,266 63,405,683,586,339,506,537,677,917,336,614,469,632 +0.10σ
4 1,207,174,538,310,755 1,207,174,511,946,624 30,646,080,400,063,988,730,710,678,241,334,525,952 +0.76σ
5 450,678,459,981,597 450,678,484,460,078 11,441,203,349,357,332,742,463,916,492,546,113,536 −1.15σ
6 135,203,538,624,396 135,203,545,338,023 3,432,361,004,807,181,877,746,540,043,112,022,016 −0.58σ
7 33,478,975,304,620 33,478,973,131,320 849,917,963,095,110,807,779,068,966,638,452,736 +0.38σ
8 6,974,786,121,476 6,974,786,069,025 177,066,242,311,482,764,899,623,415,513,612,288 +0.02σ
9 1,239,960,351,012 1,239,961,967,827 31,478,443,077,596,722,717,297,399,482,548,224 −1.45σ
10 190,127,877,980 190,127,501,733 4,826,694,605,231,472,680,134,298,812,022,784 +0.86σ
11 25,350,404,361 25,350,333,564 643,559,280,697,530,613,021,776,860,413,952 +0.44σ
12 2,957,546,449 2,957,538,916 75,081,916,081,379,203,224,115,032,883,200 +0.14σ
13 303,370,633 303,337,325 7,700,709,341,679,872,637,146,343,931,904 +1.91σ
14 27,440,953 27,444,806 696,730,845,199,615,551,711,505,022,976 −0.74σ
15 2,197,077 2,195,584 55,738,467,615,969,043,937,843,216,384 +1.01σ
16 155,492 155,521 3,948,141,456,131,134,161,795,678,208 −0.07σ
17 9,652 9,758 247,726,522,737,639,952,775,905,280 −1.07σ
18 556 542 13,762,584,596,535,593,972,793,344 +0.60σ
19 26 27 676,056,787,198,236,050,849,792 −0.12σ
20 0 1 29,295,794,111,923,550,683,136 −1.07σ
21 0 0 1,116,030,251,882,795,630,592 −0.21σ
22 0 0 37,201,008,396,093,366,272 −0.04σ
23 0 0 1,078,290,098,437,485,696 −0.01σ
24 0 0 26,957,252,460,937,684 −0.00σ
25 0 0 575,088,052,499,991 −0.00σ
26 0 0 10,322,093,250,000 −0.00σ
27 0 0 152,919,900,000 −0.00σ
28 0 0 1,820,475,000 −0.00σ
29 0 0 16,740,000 −0.00σ
30 0 0 111,600 −0.00σ
31 0 0 480 −0.00σ
32 0 0 1 −0.00σ