Hello Stan community,

I am trying to fit a mediation model using generalised linear mixed models in brms. I used the R package mediation before but I would like to use bayesian methods for all my analysis and thus I am trying to fit my models with brms:

corloc -> binary outcome variable (0|1) declared as numeric

sayyes -> binary mediator(0|1) declared as numeric

stimabs -> categorical predictor variable (7 levels) declared as factor

m1 <- bf(sayyes~ 1 + stimabs+ (1|subject), family = binomial)

m2 <- bf(corloc ~ 1 + stimabs*sayyes+ (1|subject), family = binomial)

mediation.model<- brm(m1 + m2 + set_rescor(FALSE), data = sensorydec, cores = 4)

I get the following output/error:

Using the maximum response value as the number of trials.

Only 2 levels detected so that family ‘bernoulli’ might be a more efficient choice.

Using the maximum response value as the number of trials.

Only 2 levels detected so that family ‘bernoulli’ might be a more efficient choice.

Compiling Stan program…

Start sampling

…

Warnings:

1: Using ‘binomial’ families without specifying ‘trials’ on the left-hand side of the model formula is deprecated.

2: Using ‘binomial’ families without specifying ‘trials’ on the left-hand side of the model formula is deprecated.

3: In file.remove(c(unprocessed, processed)) :

can’t delete ‘C:\Users\carina\AppData\Local\Temp\RtmpEFbaxi\file3e941c822587.stan’. reason ‘No such file or directory’

Anyone ever encountered that error? I used brms before and never had any issues. Also the model fitting seems to work, I only get that error after sampling is done.

Thank you for any help,

Carina