expression:
    a = 1;
    b = 1;
    beta = exp(theta)/(1+exp(theta));
    logdens = lgamma(a+b)-lgamma(a)-lgamma(b)+(a-1)*log(beta)+(b-1)*log(1-beta);
    log_jacobian = log(beta*(1-beta));
    return(logdens+log_jacobian)

inla(formula = formula, family = "poisson", data = data.INLA.C$`l=1`,
E = E, lincomb = beta.lc, control.compute = list(dic = TRUE,
cpo = TRUE, waic = TRUE), control.predictor = list(compute = TRUE,
cdf = c(log(1))), control.inla = list(strategy = "simplified.laplace"))