rt](i,j) is the duration of time that individuals i and j coexisted within the neighborhood of r and the time interval t; KP(i,j) is the kin proximity which describes the degree of kinship
between the family members i and j.
A recipient of a live-organ donor is restricted to the one who is the spouse, lineal relative to by blood of, and collateral relative by blood onto the third degree of kinship
with the live organ donor.
Scientists have mused that inbreeding might also create an extraordinary degree of kinship
among the two species of mole-rats that live in supersocial colonies.
Her assumption (for example) that Jacob's marriage, falling as it does at exactly the right degree of kinship
, "should offer the ideal model for the people of Israel," rather than involving Jacob in yet another relationship of deceit, competition, and conflict with his father-in-law, seems to hope for anthropology to override personality.
As the relative proportions are not always obvious, it remains somewhat arbitrary where the essential affiliation may be said to lie, especially since the degree of kinship
among disciplines varies greatly: sociology and social psychology are consanguineous, but geology and social geography are far less so, despite appearances.