| Gender | Categorical | Reference category: Male |
| Race/ethnicity | Categorical | Reference category: White |
| Citizenship | Categorical | Reference category: US citizen or permanent resident |
| Major | Categorical | Reference category: Social sciences – Anthropology; STEM – Engineering |
| Age at degree | Continuous | Age doctoral degree is awarded |
| Degree year | Continuous | Academic year doctoral degree is awarded |
| Time to degree | Continuous | Number of years between doctoral program entry and completion |
| Prev. Postdoc | Continuous | Average fraction of doctorate recipients in the same department in the five previous cohorts with initial placement as postdoc |
| Prev. Academia | Continuous | Average fraction of doctorate recipients in the same department in the five previous cohorts with initial placement in academia (including tenure track and non-tenure track positions) |
| Prev. Industry | Continuous | Average fraction of doctorate recipients in the same department in the five previous cohorts with initial placement in industry |
| Prev. Government | Continuous | Average fraction of doctorate recipients in the same department in the five previous cohorts with initial placement in the governments |
| Primary financial support | Categorical | Reference category: Other support |
| Graduation term | Categorical | Term that doctoral degree is granted – Fall (December–January); Spring/Summer (May–August); Other (all other months). Reference category: Fall |
| NRC program ranking | Categorical | Ranking of doctoral program’s research activity within its subfield group by the NRC. Reference category: Not ranked |
| Father/mother’s education level | Categorical | Reference category: High school or unknown |
| Marital status | Binary | =1: Married at the time of doctorate awarded |
| Dependent < 6 at Grad. | Categorical | Reference category: Have no child below age six in the household at the time of doctorate receipt |