We propose a new statistical test for the residual autocorrelation in ARX
adaptive tracking. The introduction of a persistent excitation in the adaptive
tracking control allows us to build a bilateral statistical test based on the
well-known Durbin-Watson statistic. We establish the almost sure convergence
and the asymptotic normality for the Durbin-Watson statistic leading to a
powerful serial correlation test. Numerical experiments illustrate the good
performances of our statistical test procedure