“The Use of Bayes Coefficients to Assess the Racial Bias-Hair Analysis Conjecture for Detection of Cocaine in Hair Samples,” by Tom Mieczkowski, Chris Sullivan, and Michael Kruger, published in the April 2007 issue of Forensic Science Communications, contained a typographical error. Under the heading “Urinalysis Data and Hair Analysis Data,” Bayes’ theorem was expressed as follows:
P(A|B) = [P(B|A)P(A) ÷ P(B|A)P(A)] + P(B|Ac)P(Ac).
The equation should have been expressed as follows:
P(A|B) = P(B|A)P(A) ÷ [P(B|A)P(A) + P(B|Ac)P(Ac)].
The editors apologize for the error.