brms:：brm-根据函数定义一些起始值

我想为

brms:：brm

模型手动设置起始值（而不是：优先级），仅针对某些系数并根据函数设置

我当前的代码如下所示（您可以忽略

x

变量和

unit

，我只想操作

z

和

as.factorF1

和

as.factorF2

的起始值）：

另一个类似的问题没有得到回答，也没有明确要求为某些系数起始值调用函数

我只找到了

inits=“0”

（将所有起始值设置为0）或默认值

inits=“random”

。有人能建议怎么做吗？提前谢谢

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")

 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