Dear All
I am currently applying Generalized Linear Models for plant
species-environment modelling.
These models contain continuous variables, factors and an interaction term
between a factor and a continuous variable. Because the variables in this
interaction term only make sense as "interaction" they are modelled as
x1:x2 (as opposed to x1*x2)
with x1 = factor and x2 = continuous variable. This results in one
coefficient for each factor level.
My question is which contrasts are used for the factor in the interaction
term. Contrasts are well documented for factors, but I cannot find a
reference for a factor:continuous variable interaction.
Thanks,
Ana
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