Table 1. Family relationships and coefficient of relationship
| Degree of relationship | Types of relative pairs | Coefficient of relationship (2Φ) |
|---|---|---|
| 1 | Parent/child, siblings | 1/2 = 0.5 |
| 2 | Grandparent/grandchild, half-sibling, avuncular (aunt or uncle with niece or nephew) | 1/4 = 0.25 |
| 3 | Great-grandparent/great-grandchild, half-avuncular, grand avuncular, first cousins | 1/8 = 0.125 |
| 4 | Great-great-grandparent/great-great-grandchild, half-grand avuncular, great-grand avuncular, first cousins once removed | 1/16 = 0.0625 |
