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Match count (byte)

Fit to analytical expectation

Expected distribution assumes MD5 acts like a random function. The matching-byte count is Binomial(16, 1/256): each of the 16 output bytes matches its input byte independently with probability 1/256.

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 0.062 0.063
Std. deviation 0.250 0.250

Pearson χ² test

Samples 11,625,578,822,107,136
Reduced χ² 1.288
Degrees of freedom 8
p-value 0.245

Per-bucket detail

Bucket Observed Expected (now) Expected (end) Residual
0 10,919,884,114,744,805 10,919,884,051,268,710 319,626,579,315,078,477,702,860,203,058,987,532,288 +0.61σ
1 685,169,136,370,592 685,169,195,373,726 20,055,001,055,063,831,456,466,004,705,206,599,680 −2.25σ
2 20,152,031,267,625 20,152,035,158,051 589,852,972,207,761,198,416,652,048,739,074,048 −0.87σ
3 368,794,875,483 368,795,414,657 10,794,694,916,220,392,661,616,333,793,787,904 −0.89σ
4 4,700,297,284 4,700,333,716 137,579,445,010,652,283,251,277,038,616,576 −0.53σ
5 44,231,465 44,238,435 1,294,865,364,806,139,908,717,484,703,744 −1.05σ
6 318,092 318,054 9,309,489,550,893,809,600,699,564,032 +0.07σ
7 1,786 1,782 52,154,003,086,240,170,526,113,792 +0.10σ
8 4 8 230,091,190,086,352,270,000,128 −1.38σ
9 0 0 802,060,793,329,338,155,008 −0.17σ
10 0 0 2,201,735,511,100,130,816 −0.01σ
11 0 0 4,709,594,676,149,986 −0.00σ
12 0 0 7,695,416,137,500 −0.00σ
13 0 0 9,285,570,000 −0.00σ
14 0 0 7,803,000 −0.00σ
15 0 0 4,080 −0.00σ
16 0 0 1 −0.00σ