Table 1.
Analysis of deviance in logistic regression for the probability that a mother will wean an offspring. (Models predict the log odds ratio of weaned/failed. MM, maternal mass at time of swapping; MCI, maternal condition index at time of swapping; BS, offspring sex birthed by a mother; FS, offspring sex fostered by a mother. Asterisk denotes significant.)
| deviance | models compared | G | Δdf | p | |
|---|---|---|---|---|---|
| model selection | |||||
| 1. null model | 43.22 | ||||
| 2. full model: WS = MM + MCI + BS + FS + BS*FS | 27.82 | 2 versus 1 | 15.4 | 5 | 0.009* |
| 3. WS = (2) − MCI | 34.34 | 3 versus 2 | 6.52 | 1 | 0.01* |
| 4. WS = (2) − MM | 34.50 | 4 versus 2 | 6.68 | 1 | 0.01* |
| 5. WS = (2) − BS*FS | 28.50 | 5 versus 2 | 0.68 | 1 | 0.41 |
| 6. WS = (5) − FS | 28.62 | 6 versus 5 | 0.12 | 1 | 0.73 |
| 7. WS = (6) − BS | 36.76 | 7 versus 6 | 8.14 | 1 | 0.004* |
| model selected: WS = MM + MCI + BS | |||||
| variable | estimate |
s.e. |
|||
| MM | 0.006 | 0.003 | |||
| MCI | −22.53 | 11.68 | |||
| BS (female) | −1.36 | 0.57 | |||