The problem of restricted random walks of fixed dimension and finite memory is considered using extension of methods discussed earlier. Inversion of recursion relations, derived in Ref. 1, is derived and recursion relations for restricted random walks of fixed dimension and four and six step...

A new formula for the mean squared error of a unit root estimator is derived. Its minimization gives rise to an estimator which is almost unbiased, unlike the maximum likelihood estimator. For this reason, it is suggested that the problem of testing for unit roots may be solved more...