# Solved – R interpretation summary (hurdle model)

I have litte experience with GLMM's and I need to use Hurdle models for the first time. I'm not sure if I interpret the output correct. Also, are there any other parameters from the summary I should check before making conclusions?

Data
Counts of insects caught in traps with 2 different luring products (A & B). The traps were emptied every 3-4 days for a few months. The sex and morph of the insects was determined. The df looks like this:

``Date       value  morph sex product 2016-04-05     5 Winter   M     A 2016-04-05     1 Summer   M     A 2016-04-05    18 Winter   F     A 2016-04-05     3 Summer   F     A ... ``

The main questions are: Which product is better? Does this differ between morphs?

Model Because of excess zeros I used a Hurdle model. I have Date as random effect. The function`glmmADMB::glmmadmb()` can make hurdle models with mixed effects. For the truncated part neg.bin. was a lot better than poisson with AIC 890 vs 1400. After comparing AIC's, these are my final models:

``# binairy part hurP1 <- glmmadmb(as.numeric(data2\$value > 0) ~ product * morph + (1 | Date),                    data = data2, family = "binomial")  # truncated part hurP2 <- glmmadmb(value ~ product * morph + sex + (1 | Date),                   data = subset(data2, value > 0), family = "truncnbinom1") ``

Summary

``# binairy part Coefficients:                    Estimate Std. Error z value Pr(>|z|)   (Intercept)              0.0946     0.4612    0.21    0.838   productB                -1.0569     0.4513   -2.34    0.019 * morphWinter              0.1898     0.4361    0.44    0.663   productB:morphWinter    -1.4064     0.6574   -2.14    0.032 *  # truncated part Coefficients:                        Estimate Std. Error z value Pr(>|z|)     (Intercept)               2.473      0.210   11.76  < 2e-16 *** sexM                      0.436      0.134    3.25  0.00117 **  productB                 -0.105      0.161   -0.66  0.51245     morphWinter              -0.719      0.189   -3.80  0.00015 *** productB:morphWinter     -0.619      0.324   -1.91  0.05569 . ``

My interpretation From the binairy model I understand there are less often insects caught (regardless of number) in B traps and this result is even stronger for winter morphs. The truncated model I find more difficult. Anyway I do understand that 1) significantly more males are caught 2) sign. less winter morphs are caught. I assume the intercept means that I have the highest number of summer females in product A?

Am I interpreting it correct? Any corrections and other insights are welcome!

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