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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 11,625,664,721,453,056
Reduced χ² 0.567
Degrees of freedom 19
p-value 0.931

Per-bucket detail

Bucket Observed Expected (now) Expected (end) Residual
0 1,474,003,880,164,753 1,474,003,920,858,940 43,143,988,327,398,911,839,001,592,649,134,112,768 −1.06σ
1 3,144,541,742,445,140 3,144,541,697,832,391 92,040,508,431,783,893,168,652,104,264,117,649,408 +0.80σ
2 3,249,359,741,056,374 3,249,359,754,426,762 95,108,525,379,508,778,125,135,623,301,109,907,456 −0.23σ
3 2,166,239,855,332,298 2,166,239,836,284,519 63,405,683,586,339,506,537,677,917,336,614,469,632 +0.41σ
4 1,047,015,932,130,425 1,047,015,920,870,847 30,646,080,400,063,988,730,710,678,241,334,525,952 +0.35σ
5 390,885,929,728,209 390,885,943,791,787 11,441,203,349,357,332,742,463,916,492,546,113,536 −0.71σ
6 117,265,775,675,466 117,265,783,137,535 3,432,361,004,807,181,877,746,540,043,112,022,016 −0.69σ
7 29,037,243,625,278 29,037,241,538,818 849,917,963,095,110,807,779,068,966,638,452,736 +0.39σ
8 6,049,425,207,111 6,049,425,320,587 177,066,242,311,482,764,899,623,415,513,612,288 −0.05σ
9 1,075,451,733,880 1,075,453,390,327 31,478,443,077,596,722,717,297,399,482,548,224 −1.60σ
10 164,903,108,887 164,902,853,183 4,826,694,605,231,472,680,134,298,812,022,784 +0.63σ
11 21,987,117,092 21,987,047,091 643,559,280,697,530,613,021,776,860,413,952 +0.47σ
12 2,565,168,217 2,565,155,494 75,081,916,081,379,203,224,115,032,883,200 +0.25σ
13 263,114,577 263,092,871 7,700,709,341,679,872,637,146,343,931,904 +1.34σ
14 23,796,592 23,803,641 696,730,845,199,615,551,711,505,022,976 −1.44σ
15 1,904,937 1,904,291 55,738,467,615,969,043,937,843,216,384 +0.47σ
16 134,895 134,887 3,948,141,456,131,134,161,795,678,208 +0.02σ
17 8,426 8,464 247,726,522,737,639,952,775,905,280 −0.41σ
18 475 470 13,762,584,596,535,593,972,793,344 +0.22σ
19 24 23 676,056,787,198,236,050,849,792 +0.19σ
20 0 1 29,295,794,111,923,550,683,136 −1.00σ
21 0 0 1,116,030,251,882,795,630,592 −0.20σ
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