Effective degrees of freedom for spline term in glmmTMB I have fitted a model in glmmTMB that includes an spline function for age using the bs function from the splines package (version 3.6.2) in R. The syntax in glmmTMB looks like this:
glmmTMB(litter_size ~ bs(maternal_age, 3) +  prey_abundance + (1|motherID),
data = ourdata, family=poisson)
One of my colleagues suggested that I should provide the effective degrees of freedom (EDF) for the spline term when reporting the results. Is there a method to get the EDF for this term from the glmmTMB model object?
I know I can get the EDF by using the mgcv package but in this case, I prefer to use glmmTMB if possible.

The spline you included in the model isn't penalised so its EDF is 3 because that's what you set it to.
To confirm, run with(ourdata, ncol(bs(maternal_age, 3))) and check the number of columns.
