对于有界度量的先验，我试图在 [-1,1] 之间拉伸 beta 分布，“[a]s 由 Barnard, McCulloch & Meng (2000) 描述”（根据本教程）。
具体来说，我正在尝试实施这个建议：
rho_half_with ~ dbeta(1, 1)
# shifting and streching rho_half_with from [0,1] to [-1,1]
rho ~ 2 * rho_half_with - 1
但是，我总是得到
syntax error on line (...) near "2"
我发现手册中没有关于JAGS或 BUGS 的条目涉及分布操作（作为随机关系分配的来源）。是否确实可以将基本算术运算应用于 BUGS/JAGS 随机关系（遵循~运算符），如果可以，如何？
The problem with the code you have posted is that you use a ~ in a non-stochastic relation, where JAGS would want you to use <- instead. The following should work:
rho_half_with ~ dbeta(1, 1)
# shifting and streching rho_half_with from [0,1] to [-1,1]
rho <- 2 * rho_half_with - 1
Regarding the error message you mention in the comments you get that because you try to initiate a variable that is not stochastic (rho). Remove that initialization or switch to initializing rho_half_with to solve that problem.