Non-centered parameterisation with boundaries

Modeling
5

Just look at the implied boundaries. We require p_sub > 0, and have

p_sub = p_group_mu + p_group_sd * p_sub_raw;

so that implies

p_group_mu + p_group_sd * p_sub_raw > 0

or

p_sub_raw > -p_group_mu / p_group_sd

So the answer is that if you have <lower = -p_group_mu / p_group_sd>, then it will guarantee that p_sub > 0.

But you may want to model this another way.

4 Likes