Use Kinship From Path when you need to compute one common-ancestor path contribution to the kinship coefficient as (1/2)^(n₁+n₂+1) × (1+Fₐ), where the path length is the combined generations from both individuals to the ancestor. Enter Common ancestor inbreeding and Path length using the definitions and units below so the result can be reproduced.

Common ancestor inbreeding

A finite measured or assumed value from 0 through 1.

Path length

Number of generations on the connecting pedigree path.

The published tool contract uses this rule: Compute one common-ancestor path contribution to the kinship coefficient as (1/2)^(n₁+n₂+1) × (1+Fₐ), where the path length is the combined generations from both individuals to the ancestor.

Kinship coefficient

The calculated kinship coefficient.

A ratio or percentage can conceal the scale of its numerator and denominator and becomes sensitive to measurement error when the denominator is small. Common ancestor inbreeding must remain between 0 and 1.

Retain the original Common ancestor inbreeding and Path length values and their units alongside the result. Additive Relationship is useful when you instead need to compute the additive relationship contribution of one common ancestor path as the number of paths times 0.5 raised to the generation distance. Pedigree F Accumulated provides another view by helping you accumulate an inbreeding coefficient as the base coefficient plus the remaining relationship budget times one path contribution.

• Additive Relationship

  Compute the additive relationship contribution of one common ancestor path as the number of paths times 0.5 raised to the generation distance.

• Pedigree F Accumulated

  Accumulate an inbreeding coefficient as the base coefficient plus the remaining relationship budget times one path contribution.

• Coancestry Coefficient

  Compute the coancestry or kinship phi of two individuals as half of their additive relationship coefficient.