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Essen-Moller W

Definition

The formula for probability of paternity derived by Erik Essen-Moller in 1938 and widely adopted by forensic laboratories. W = CPI / (CPI + 1) when the prior probability is 0.5. Still the standard conversion used for serological and DNA paternity reports.

Related terms

Combined paternity index (CPI)
The product of all individual paternity indices across all marker systems tested. Assumes independence of the marker systems. The CPI is a...
Exclusion probability (W)
The proportion of the male reference population that would be excluded as the biological father by the marker panel tested. A high...
Obligatory paternal allele
The allele a child must have received from the biological father, identified by subtracting the mother's alleles from the child's genotype. The...
Paternity index (PI)
A likelihood ratio that compares the probability of the observed serological profile if the alleged father is the biological father to the...
Probability of paternity (W)
The posterior probability that the alleged father is the biological father, calculated from the CPI and a prior probability using Bayes' theorem....

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