Specifying different priors for different coefficients in RStanARM?

Is there a way to specify different priors in RStanARM?
In Stan, you can do x1 ~ normal(0,1), x2 ~ normal(0,3), etc…
I do not see a way to do that in RStanARM- only prior, prior_intercept and prior_aux.

It is like

prior = normal(location = 0, scale = c(1, 3))

perhaps with auto_scale = FALSE.

Yeah it’s like @bgoodri said.

kickstarter_priors <- normal(location = c(-1, 0.5, 0.5),
scale = c(0.5, 0.5, 0.5), autoscale = FALSE)

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I presume, in general, parameters have to be sorted alphabetically in order to related them to coefficients? It is not possible to provide named vectors or lists for location or scale?

They variables don’t have to be sorted alphabetically, but the priors do take vectors only (possibly with recycling). So, the vectors different locations and / or scales have to be in the same order as the predictors in the model.

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Sorry, what you mean by „in the same order as the predictors in the model“? Would this mean that in a model

outcome ~ Z + Y + X + (W | ID)

I would specify (say) in the location vector the location for Z,Y,X at the 1st, 2nd and 3rd position, respectively?

Yes

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