Hi all,

I would like to set starting values for a `brms::brm`

model manually for some coefficients only and according to a function (runif).

My current code looks something like this (you can ignore `x`

variables and `unit`

, I just want to manipulate the starting values of `z`

and of `"as.factorFa1`

and `"as.factorFa2`

):

```
library(tidyverse)
library(brms)
df <- data.frame(x1 = rnorm(100, mean = 1, sd = 2),
x2 = rnorm(100, mean = 2, sd = 2),
x3 = rnorm(100, mean = 3, sd = 2),
z = rnorm(100, mean = 4, sd = 2),
Fa = wakefield::r_sample_factor(n = 100, x = c(1, 2, 3)),
unit = wakefield::r_sample_factor(n = 100, x = 1:10),
Y = rnorm(100, mean = 15, sd = 5)
) %>% tibble::tibble()
brmsmodel <- brm(Y ~ as.factor(Fa) + # Fa has levels 1, 2, 3
x1 + x2 + x3 + z + (1 + x1 | unit),
data = df,
prior = c(prior(normal(0, 1), class = "b", coef = "z"),
prior_string("normal(0, 1)", class = "b", coef = paste("as.factorFa", 2:3, sep=""))),
chains = 1, iter = 25, warmup = 10, seed = 123,
init = "0")
```

This code works; however, I would like to set some starting values (`inits`

) manually to be drawn from a uniform distribution `(X ~ U[0,1])`

, similar to the priors.

I want something like this (pseudo code)

```
inits: 1) init = runif(0, 1), class = "b", coef = "z"
2) init = runif(0, 1), class = "b", coef = "as.factorFa2"
3) init = runif(0, 1), class = "b", coef = "as.factorFa2"
other inits: random
```

I only found `inits = "0"`

(to set all starting values to 0) or the default `inits = "random"`

. Can someone advise how to do this? Thanks in advance!