Table 2. The top-ranked set of ordinal regression models relating leaf damage of A. hippocastanum with the number of years that C. ohridella was predicted to have been present.
Model type* | Number of C. ohridella | Break-point | ΔAIC | AIC |
generations to model distribution† | (years) | weight | ||
Log-linear segmented | 2-generation model | 3 | 0 | 0.395 |
Linear segmented | 2-generation model | 3 | 0.4 | 0.319 |
Linear segmented | 3-generation model | 4 | 2.7 | 0.105 |
Log-linear segmented | 2-generation model | 4 | 4.0 | 0.053 |
Log-linear segmented | 3-generation model | 4 | 4.7 | 0.038 |
Log-linear segmented | 2-generation model | 7 | 6.1 | 0.019 |
Log-linear segmented | 2-generation model | n/a | 6.2 | 0.018 |
Log-linear segmented | 2-generation model | 6 | 6.9 | 0.013 |
Log-linear segmented | 2-generation model | 2 | 8.5 | 0.006 |
Linear segmented | 2-generation model | 2 | 8.5 | 0.006 |
Log-linear segmented | 3-generation model | 7 | 8.6 | 0.005 |
Linear | 3-generation model | n/a | 9.0 | 0.004 |
Log-linear | 3-generation model | n/a | 9.0 | 0.004 |
Log-linear segmented | 3-generation model | 6 | 9.1 | 0.004 |
Log-linear segmented | 2-generation model | 5 | 9.5 | 0.003 |
Linear segmented | 2-generation model | 4 | 9.6 | 0.003 |
Models are ordered by relative model fit (ΔAIC) and only those with ΔAIC<10 are shown here.
The form of the relationship of years present with leaf damage. The segmented regression models show a linear or log-linear relationship up to the break-point, after which the relationship is constant.
All the top-ranked regression models were based on the modeled distribution of C. ohridella, assuming either 2 or 3 generations per year. Regression models including the directly observed year of arrival were included in the candidate model set, but all had ΔAIC>10.7, so are not shown here.