An Index of Genealogical Relatedness Derived from a Genetic Model

Abstract

The coefficient de parente $\sigma(x, y)$ of Malecot, which measures the genealogical relatedness of individuals $x$ and $y$, is derived as a correlation coefficient of certain genotype scores. An explicit formula is given for $\sigma(x, y)$ involving path sums in the ancestral charts of $x$ and $y$. The expected value of $\sigma(x, y)$ is worked out for certain random population models.