Please also provide the following information in addition to your question:

- Operating System: Windows 10
- brms Version: 2.8

This might be a very basic question, but I realized I am a little confused about the output of get_prior().

So I used the get_prior() function for my model:

get_prior(bf(Y ~ 100 + (A-100) / (1 + exp ((B-t) / C)),

A~ 1 + (1|ID),

B ~ 1 + (1|ID),

C ~ 1,

nl = TRUE), data = Data)

The output I get from it is the following:

I am still a bit confused about what the meaning of Prior 2.

Why do we need Prior 2, if we have Prior 3? Do they not somehow express the same thing? Also, I am not sure I clearly understand the meaning of Prior 4 - standard deviation of the distribution of a population effect?

Or is Prior 2 somewhat of a combination of 3 and 4?

I read this, but I didnâ€™t find anything about prior 4, and as to the other two, it seems like something similar to Prior 2 was explained for population effects, but then left me wondering about why we would need Prior 3.

Any help would be appreciated!