Table 2.

Parameter estimates (mean value of posterior distributions) for zero-inflated Poisson model explaining interaction counts at fine resolution. Parameters are consistent with the definition given in equations (2.1)–(2.3), and those in bold are statistically significant. Values in parentheses are s.d. of the parameter estimate; values in brackets are 95% credible intervals. Bayesian posteriors were calculated as in table 1. The model includes seven parameters (α₀ and α₁ are omitted for clarity) and is run separately for each combination of treatments.

parameter	control	temp.	nitrogen	temp. + N
intercept: β0	−6.81 (1.51) [−9.99, −4.01]	−6.74 (1.40) [−9.56, −4.05]	−6.11 (1.09) [-8.31, −4.07]	−4.77 (1.32) [−7.48, −2.28]
host density: β1	1.21 (0.15) [0.91, 1.53]	1.17 (0.14) [0.91, 1.46]	1.26 (0.17) [0.92, 1.61]	1.43 (0.14) [1.15, 1.72]
parasitoid density: β2	1.64 (0.22) [1.24, 2.09]	1.57 (0.17) [1.25, 1.94]	1.54 (0.16) [1.23, 1.88]	1.79 (0.18) [1.45, 2.17]
host body size: β3	0.36 (0.48) [−0.53, 1.36]	0.61 (0.36) [−0.07, 1.36]	0.31 (0.27) [−0.21, 0.87]	1.27 (0.40) [0.52, 2.11]
parasitoid body size: β4	−0.21 (0.18) [−0.58, 0.14]	−0.21 (0.17) [−0.55, 0.10]	−0.06 (0.12) [−0.32, 0.18]	0.02 (0.16) [−0.30, 0.33]