Table 2. Multivariate logistic regression results modeling physics Ph.D. completion in four analytic samples.
The coefficients for logit and odds ratios (ORs) for Ph.D. completion are reported, along with their SEs. Tier 1 (highest ranked, NRC-R ≤ 20), Tier 2 (25 ≤ NRC-R ≤ 55), and Tier 3 (NRC-R > 55). Reference groups are Tier 3 for ranking and White for race/ethnicity. *P < 0.05; **P < 0.01; ***P < 0.001.
| All students | U.S. only | U.S. female | U.S. male | |||||
| (N = 3962) | (N = 2315) | (N = 402) | (N = 1913) | |||||
| Logit | OR | Logit | OR | Logit | OR | Logit | OR | |
| (SE) | (SE) | (SE) | (SE) | (SE) | (SE) | (SE) | (SE) | |
| (Intercept) | −1.63** (0.53) |
0.2** (0.1) |
−2.63*** (0.69) |
0.07*** (0.05) |
−4.46** (1.65) |
1 × 10−2** (0.02) |
−2.05** (0.77) |
0.1** (0.1) |
| UGPA | 0.31* (0.12) |
1.4* (0.2) |
0.60*** (0.16) |
1.8*** (0.3) |
0.9* (0.4) |
2.5* (1) |
0.47* (0.18) |
1.6* (0.3) |
| GRE-Q | 13 × 10−3** (4 × 10−3) |
1.013** (0.004) |
10 × 10−3* (5 × 10−3) |
1.011* (0.005) |
0.017 (0.012) |
1.02 (0.01) |
0.01 (6 × 10−3) |
1.010 (0.006) |
| GRE-V | −1 × 10−3 (2 × 10−3) |
0.999 (0.002) |
−1 × 10−4 (3 × 10−3) |
0.9999 (0.003) |
−1 × 10−3 (7 × 10−3) |
0.999 (7 × 10−3) |
−5 × 10−6 (3 × 10−3) |
1.000 (0.003) |
| GRE-P | 3 × 10−3 (2 × 10−3) |
1.004 (0.002) |
5 × 10−3 (3 × 10−3) |
1.005 (0.003) |
2 × 10−4 (6 × 10−3) |
1.000 (0.006) |
5 × 10−3 (3 × 10−3) |
1.005 (0.003) |
| Tier 1 | 0.69*** (0.1) |
2.0*** (0.2) |
0.73*** (0.14) |
2.1*** (0.3) |
0.90** (0.34) |
2.5** (0.8) |
0.74*** (0.15) |
2.1*** (0.3) |
| Tier 2 | 0.23* (0.1) |
1.3* (0.1) |
0.53*** (0.13) |
1.7*** (0.2) |
0.15 (0.3) |
1.2 (0.4) |
0.63*** (0.15) |
1.9*** (0.3) |
| Asian | −0.02 (0.28) |
1.0 (0.3) |
−0.01 (0.28) |
0.99 (0.28) |
0.09 (0.51) |
1.1 (0.6) |
−0.07 (0.34) |
0.9 (0.3) |
| Black | −0.77* (0.39) |
0.5* (0.2) |
−0.72 (0.39) |
0.49 (0.19) |
−1.08 (1.02) |
0.3 (0.3) |
−0.65 (0.44) |
0.5 (0.2) |
| Hispanic | −0.60* (0.30) |
0.5* (0.2) |
−0.56 (0.3) |
0.57 (0.17) |
0.58 (0.87) |
1.8 (1.6) |
−0.77* (0.33) |
0.5* (0.2) |
| Native | −15 (240) |
0 (0) |
−15 (240) |
0 (0) |
−15 (880) |
0 (0) |
−15 (270) |
0 (0) |
| Other | −1.2* (0.5) |
0.3* (0.1) |
−1.14* (0.48) |
0.32* (0.15) |
−0.62 (0.95) |
0.5 | −1.29* (0.56) |
0.3* (0.2) |
| Undisclosed | −0.25* (0.1) |
0.8* (0.1) |
−0.35** (0.13) |
0.7** (0.09) |
−0.21 (0.29) |
0.8 (0.2) |
−0.39** (0.14) |
0.7** (0.1) |
| Female | −0.16 (0.1) |
0.9 (0.1) |
−0.22 (0.13) |
0.8 (0.11) |
||||
| Non-U.S. | 0.09 (0.1) |
0.9 (0.1) |
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