[R-sig-ME] interaction terms interpretation

[Joaquín Aldabe]

Hi all, I´m running a mixed model with poisson error distribution as I have
count data of a shorebird species. My predictors are AMGP (another
shorebird that is usually associated to "my" species and probably has
ecological influence on it), grass height and field distance to the lagoon.

I´m having a hard time trying to interpret second order interactions. I
appreciate your comments of references recommendations. Here is the output
of my model. All the best, Joaquín.

Call:glmmadmb(formula = BBSA ~ AMGP * Grass_height *
Distance_to_lagoon +     (1 | Field_name) + offset(log(Field_area.o)),
data = my4S,     family = "nbinom1", zeroInflation = TRUE)
AIC: 226
Coefficients:                                     Estimate Std. Error
z value Pr(>|z|)    (Intercept)                           -5.8797
1.2250   -4.80  1.6e-06 ***AMGP
3.3086     1.0246    3.23   0.0012 ** Grass_height
     -4.1592     1.9961   -2.08   0.0372 *  Distance_to_lagoon
           -0.5029     1.3929   -0.36   0.7180    AMGP:Grass_height
                  2.9442     1.5142    1.94   0.0518 .
AMGP:Distance_to_lagoon               -2.4695     0.9632   -2.56
0.0104 *  Grass_height:Distance_to_lagoon        0.0339     2.0065
0.02   0.9865    AMGP:Grass_height:Distance_to_lagoon  -4.0363
1.3264   -3.04   0.0023 ** ---Signif. codes:  0 ‘***’ 0.001 ‘**’ 0.01
‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1
Number of observations: total=64, Field_name=16 Random effect
variance(s):Group=Field_name            Variance StdDev(Intercept)
0.03721 0.1929
Negative binomial dispersion parameter: 20.633 (std. err.:
7.4042)Zero-inflation: 1e-06  (std. err.:  6.8336e-09 )
Log-likelihood: -102


-- 
*Joaquín Aldabe*

*Grupo Biodiversidad, Ambiente y Sociedad*
Centro Universitario de la Región Este, Universidad de la República
Ruta 15 (y Ruta 9), Km 28.500, Departamento de Rocha

*Departamento de Conservación*
Aves Uruguay
BirdLife International
Canelones 1164, Montevideo

https://sites.google.com/site/joaquin.aldabe
<https://sites.google.com/site/perfilprofesionaljoaquinaldabe>

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