Table 2.
Model selection results of the analysis of breeding territories vs. control areas (n = 73 pairs)
| Hypothesis | Variables in model | LL | K | AICc | ΔAICc | Weight |
|---|---|---|---|---|---|---|
| Forest structure | ||||||
| (a) Ground variables | Number of bushes, number of tussocks, cover of herb layer2 | −77.238 | 7 | 169.288 | 0 | 0.232 |
| Number of bushes, year, number of bushes x year, number of tussocks | −75.155 | 9 | 169.633 | 0.345 | 0.195 | |
| Number of bushes, number of tussocks | −80.208 | 5 | 170.845 | 1.557 | 0.106 | |
| Number of bushes, number of tussocks2, cover of herb layer2 | −77.089 | 8 | 171.230 | 1.942 | 0.088 | |
| … | ||||||
| Null | −101.199 | 3 | 208.568 | 39.280 | 0.000 | |
| (b) Tree variables | Number of trees, tree dbh | −87.397 | 5 | 185.224 | 0 | 0.158 |
| Number of trees, tree dbh, tree species diversity2 | −85.854 | 7 | 186.520 | 1.297 | 0.083 | |
| Number of trees, tree dbh, tree species diversity | −87.160 | 6 | 186.924 | 1.701 | 0.068 | |
| … | ||||||
| Null | −101.199 | 3 | 208.568 | 23.345 | 0.000 | |
| (c) Tree species composition | Null | −101.199 | 3 | 208.568 | 0 | 0.114 |
| Proportion beech, propoprtion other deciduous trees, proportion conifers2 | −97.099 | 7 | 209.01 | 0.442 | 0.091 | |
| Proportion beech, propoprtion other deciduous trees, proportion conifers | −98.227 | 6 | 209.059 | 0.491 | 0.089 | |
| Proportion beech | −100.459 | 4 | 209.202 | 0.634 | 0.083 | |
| Proportion beech2, propoprtion other deciduous trees, proportion conifers2 | −96.542 | 8 | 210.134 | 1.566 | 0.052 | |
| Rodent-avoidance | Rodent numbers, year, rodent numbers x year | −93.230 | 8 | 203.511 | 0 | 0.498 |
| Rodent numbers | −98.100 | 4 | 204.483 | 0.972 | 0.306 | |
| Null | −101.199 | 3 | 208.568 | 5.057 | 0.040 | |
| Topography | Slope steepness | −91.564 | 4 | 191.412 | 0 | 0.558 |
| … | ||||||
| Null | −101.199 | 3 | 208.568 | 17.156 | 0 | |
| Across hypotheses | Slope steepness, rodent numbers, number of tussocks, cover of herb layer2, number of trees, number of bushes, tree dbh | −62.749 | 11 | 149.469 | 0 | 0.107 |
| Slope steepness, rodent numbers, number of tussocks, cover of herb layer2, number of trees, number of bushes | −63.958 | 10 | 149.545 | 0.076 | 0.103 | |
| Slope steepness, rodent numbers, number of tussocks, cover of herb layer2, number of trees, tree dbh | −64.066 | 10 | 149.762 | 0.293 | 0.092 | |
| Slope steepness, rodent numbers, number of tussocks, cover of herb layer2, number of trees | −65.448 | 9 | 150.220 | 0.751 | 0.073 | |
| Slope steepness, number of tussocks, cover of herb layer2, number of trees, number of bushes | −65.976 | 9 | 151.275 | 1.806 | 0.043 | |
| Slope steepness, rodent numbers, number of tussocks, cover of herb layer2, number of trees, tree dbh, tree species diversity2 | −62.470 | 12 | 151.285 | 1.816 | 0.043 | |
| Slope steepness, rodent numbers, number of tussocks, cover of herb layer2, number of trees, tree species diversity2 | −63.658 | 11 | 151.287 | 1.817 | 0.043 | |
| … | ||||||
| Null | −101.199 | 3 | 208.568 | 59.099 | 0.000 | |
For each hypothesis, the top-ranked model (ΔAICc = 0), the models with ΔAICc < 2 to the top-ranked model and the null model (referred to as “null”) are shown. “…” refers to additional models examined, but not listed in detail to avoid overlong table, as they were little informative
The quadratic effect of a variable x, composed of a linear and a quadratic component (x ± x2), is denoted as x2
LL log-likelihood, K number of parameters in the model (including random effects and intercept), weight Akaike weight (chance of the model to be the best one, given the candidate models)