Hey,

I’d like to build this model (Bayesian One-Sample T-Test (Stan)) in brms. Is this possible?

I can’t figure out how to put the Jeffrey’s prior on sigma2 like this: `target += log(1/sigma2); // Jeffreys prior on sigma2`

.

How can I add the equivalent prior on sigma?

I’ve tried this

```
priors <- c(prior('cauchy(0, 0.707)', class = "Intercept"),
prior_string("target += sqrt(log(1/(sigma^sigma)))", check = FALSE))
```

but it didn’t work:

model$prior

prior class coef group resp dpar nlpar bound

1 cauchy(0, 0.707) Intercept

2 student_t(3, 0, 10) sigma

3 target += sqrt(log(1/(sigma^sigma)))

Sorry if I get something horribly wrong.