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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 6,074,853,283,069,952
Reduced χ² 0.751
Degrees of freedom 19
p-value 0.768

Per-bucket detail

Bucket Observed Expected (now) Expected (end) Residual
0 770,223,274,166,633 770,223,275,178,775 43,143,988,327,398,911,839,001,592,649,134,112,768 −0.04σ
1 1,643,142,974,391,768 1,643,142,987,048,046 92,040,508,431,783,893,168,652,104,264,117,649,408 −0.31σ
2 1,697,914,380,235,944 1,697,914,419,949,625 95,108,525,379,508,778,125,135,623,301,109,907,456 −0.96σ
3 1,131,942,988,291,561 1,131,942,946,633,089 63,405,683,586,339,506,537,677,917,336,614,469,632 +1.24σ
4 547,105,777,952,897 547,105,757,539,325 30,646,080,400,063,988,730,710,678,241,334,525,952 +0.87σ
5 204,252,803,204,147 204,252,816,148,016 11,441,203,349,357,332,742,463,916,492,546,113,536 −0.91σ
6 61,275,844,574,376 61,275,844,844,405 3,432,361,004,807,181,877,746,540,043,112,022,016 −0.03σ
7 15,173,071,366,746 15,173,066,342,424 849,917,963,095,110,807,779,068,966,638,452,736 +1.29σ
8 3,161,055,700,667 3,161,055,488,005 177,066,242,311,482,764,899,623,415,513,612,288 +0.12σ
9 561,964,235,095 561,965,420,090 31,478,443,077,596,722,717,297,399,482,548,224 −1.58σ
10 86,168,340,806 86,168,031,080 4,826,694,605,231,472,680,134,298,812,022,784 +1.06σ
11 11,489,202,743 11,489,070,811 643,559,280,697,530,613,021,776,860,413,952 +1.23σ
12 1,340,410,122 1,340,391,595 75,081,916,081,379,203,224,115,032,883,200 +0.51σ
13 137,490,336 137,476,061 7,700,709,341,679,872,637,146,343,931,904 +1.22σ
14 12,435,509 12,438,310 696,730,845,199,615,551,711,505,022,976 −0.79σ
15 995,477 995,065 55,738,467,615,969,043,937,843,216,384 +0.41σ
16 70,392 70,484 3,948,141,456,131,134,161,795,678,208 −0.35σ
17 4,475 4,423 247,726,522,737,639,952,775,905,280 +0.79σ
18 246 246 13,762,584,596,535,593,972,793,344 +0.02σ
19 12 12 676,056,787,198,236,050,849,792 −0.02σ
20 0 1 29,295,794,111,923,550,683,136 −0.72σ
21 0 0 1,116,030,251,882,795,630,592 −0.14σ
22 0 0 37,201,008,396,093,366,272 −0.03σ
23 0 0 1,078,290,098,437,485,696 −0.00σ
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