Hi Everyone,
A small basic question. I have a logistic regression (sampled with brms) where y is predicted by x1, x2 and their paired interaction. I want to be able to report evidence in favor of no interaction effect.
I sampled these two models and used loo to compare them:
model_h0= brm(y ~ 0 + Intercept+x1+x2+(1+x1*x2| subject),
data = df
family = bernoulli(link = "logit"),
warmup = 1000,
iter = 2000,
cores =4,
chains=4,
backend = "cmdstan",
prior=mypriors)
model_h1= brm(y ~ 0 + Intercept+x1*x2+(1+x1*x2| subject),
data = df
family = bernoulli(link = "logit"),
warmup = 1000,
iter = 2000,
cores =4,
chains=4,
backend = "cmdstan",
prior=mypriors)
model_h1=loo(model_h1)
model_h0=loo(model_h0)
loo_compare(model_h0,model_h1)
What I really want is to be able to say that “A model without the interaction population level effect was X times more likely given the data compared to a model that included the x1:x2 interaction”
How can I get there? Or maybe other ideas on how to tackle this basic report?
Many thanks,
Nitzan