Table. 2 The effects of site type (A–E; see text and legend of Fig. 1) and the likelihood of cold winter on the probability of pine sawfly damage. Parameter estimates (and standard deviation), with the p values of the tests of significance of the term, of the linear predictor of the GLM (see Eq. 1 in the “Data analysis” section) fitted on different data sets

Intercept (α, effect of B)

−3.34 (0.16)

−6.88 (0.16)

−4.48 (0.16)

Difference of A to B (β_A)

−1.17 (0.40) p = 0.003

−13.2 (185.7) p = 0.94

−1.06 (0.59) p = 0.076

Difference of C to B (β_C)

0.43 (0.17) p = 0.012

1.28 (0.14) p < 0.001

0.89 (0.17) p < 0.001

Difference of D to B (β_D)

−1.37 (1.01) p = 0.176

−0.39 (0.33) p = 0.234

−0.64 (0.59) p = 0.279

Difference of E to B (β_E)

0.91 (0.29) p = 0.002

1.19 (0.15) p < 0.001

0.45 (0.21) p = 0.030

Effect of the likelihood of cold winter (γ)

−3.75 (0.68) p < 0.001

3.80 (0.28) p < 0.001

−5.31 (0.68) p < 0.001