Several first-order autoregressive processes are studied using Bayesia
n analysis principles. These autoregressive processes are the same, ex
cept perhaps for the level of the process. A test is developed to dete
ct possible level differences by using the mean value functions of the
se first-order autoregressive processes. To illustrate the test result
s, a numerical study is conducted using two time series groups. (C) 19
98 Elsevier Science B.V.