A few problems in your code. In your model you have J and Length. In your data you have j (twice) and length, i.e. no Length or J. In your initial values you have ort which is not a parameter used anywhere in the model and tau which is not...

xij looks to be matrix in the BUGS model, but you have at as a vector in the data. This should work: list(n=2, k=5, yij=structure(.Data=c(1, 1, 1, 1, 1, 0, 0, 0, 0, 0), .Dim=c(2,5)), xij = structure(.Data=c(0.0494063719, -0.078101264, 0.2748560749, 0.1245743393, -2.531242809, .6849338859, 0.5302062384, 0.7828560148, -0.012341452, 0.5128471157), .Dim=c(2,5)), ui =...