Table 2. Results of the zero-inflated negative binomial (ZINB) regression models predicting the odds of chasmogamous and cleistogamous buds developing and expected bud counts as a function of the averaged, z-score transformed environmental variables from 2016 and 2017.
Chasmogamous ZINB | Theta = 1.68, Log-likelihood = -230 on 11 DF | |||||
Binary model (0 vs. 1 bud) | Estimate | SE | z-value | p-value | 95% CI | iExp(coef) |
Intercept | -0.04 | 0.57 | -0.08 | 0.94 | -1.16 to 1.07 | 1.04 |
Light quantity | -4.09 | 1.50 | -2.71 | 0.007 | -7.03 to -1.13 | 59.48 |
Photoperiod | 2.77 | 1.21 | 2.29 | 0.02 | 0.40 to 5.13 | 0.06 |
Mean temperature | 1.54 | 0.55 | 2.78 | 0.005 | 0.46 to 2.63 | 0.21 |
Soil moisture | -0.17 | 0.55 | -0.30 | 0.76 | -1.25 to 0.92 | 1.18 |
Count model (≥1 bud) | Exp(coef) | |||||
Intercept | 1.77 | 0.23 | 7.83 | 4.78e-15 | 1.33 to 2.21 | 5.86 |
Light quantity | -0.23 | 0.13 | -1.76 | 0.08 | -0.49 to 0.03 | 0.79 |
Photoperiod | -0.45 | 0.23 | -1.94 | 0.052 | -0.91 to 0.005 | 0.63 |
Mean temperature | -0.07 | 0.11 | -0.71 | 0.48 | -0.28 to 0.13 | 0.93 |
Soil moisture | -0.07 | 0.14 | -0.50 | 0.62 | -0.34 to 0.20 | 0.93 |
Log(theta) | 0.52 | 0.22 | 2.32 | 0.02 | - | - |
Cleistogamous ZINB | Theta = 1.04, Log-likelihood = -291.3 on 11 DF | |||||
Binary model (0 vs. 1 bud) | Estimate | SE | z-value | p-value | 95% CIs | iExp(coef) |
Intercept | -0.08 | 0.56 | -0.15 | 0.88 | -1.19 to 1.02 | 1.09 |
Light quantity | 4.21 | 1.84 | 2.30 | 0.02 | 0.61 to 7.81 | 0.01 |
Photoperiod | -2.54 | 1.47 | -1.73 | 0.08 | -5.42 to 0.34 | 12.63 |
Mean temperature | -2.10 | 1.30 | -1.60 | 0.11 | -4.61 to 0.47 | 7.92 |
Soil moisture | 1.62 | 0.78 | 2.06 | 0.04 | 0.08 to 3.15 | 0.20 |
Count model (≥1 bud) | Exp(coef) | |||||
Intercept | 2.98 | 0.29 | 10.25 | <2e-16 | 2.41 to 3.55 | 19.69 |
Light quantity | 1.00 | 0.54 | 1.87 | 0.06 | -0.05 to 2.05 | 2.73 |
Photoperiod | -0.28 | 0.28 | -1.02 | 0.31 | -0.82 to 0.26 | 0.76 |
Mean temperature | -0.75 | 0.19 | -3.88 | 1.03e-4 | -1.13 to -0.37 | 0.47 |
Soil moisture | -0.11 | 0.13 | -0.83 | 0.41 | -0.36 to 0.15 | 0.90 |
Log(theta) | 0.04 | 0.23 | 0.16 | 0.88 | - | - |
DF = degrees of freedom, SE = standard error, CI = confidence interval, iExp(coef) = inverted and exponentiated coefficients (inverted odds ratios), Exp(coef) = exponentiated count coefficients (incidence rate ratios).