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A239386
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Decimal expansion of the probability of a normal-error variable exceeding the mean by more than five standard deviations.
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7
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2, 8, 6, 6, 5, 1, 5, 7, 1, 8, 7, 9, 1, 9, 3, 9, 1, 1, 6, 7, 3, 7, 5, 2, 3, 3, 2, 8, 7, 4, 6, 4, 5, 3, 5, 3, 8, 5, 4, 4, 2, 3, 0, 1, 3, 6, 1, 1, 8, 8, 9, 5, 7, 3, 0, 8, 5, 4, 9, 2, 7, 9, 8, 9, 3, 4, 7, 5
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OFFSET
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-6,1
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COMMENTS
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The probability P{(x-m)/s > 5} for a normally distributed random variable x with mean m and standard deviation s.
In experimental sciences (hypothesis testing), a measured excursion exceeding background "noise" by more than five standard deviations is considered practically certain, unless it is an isolated case among tens of thousands of iterated measurements.
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LINKS
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FORMULA
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P{(x-m)/s > 5} = P{(x-m)/s < -5} = 0.5*erfc(5/sqrt(2)), with erfc(x) being the complementary error function.
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EXAMPLE
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2.86651571879193911673752332874645353854423013611889573...e-7
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MATHEMATICA
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First[RealDigits[1 - CDF[NormalDistribution[], 5], 10, 100]] (* Joan Ludevid, Jun 13 2022 *)
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PROG
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(PARI) n=5; a=0.5*erfc(n/sqrt(2)) \\ Use sufficient realprecision
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CROSSREFS
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KEYWORD
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AUTHOR
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STATUS
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approved
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