On sequentially adaptive asymptotically efficient rank statistics

Abstract

For the simple regression model ( containing the two—sample location model as a special case ), adaptive ( linear ) rank statistics arising in the context of ( asymtotically) efficient testing and estimation procedures are considered. An orthonormal system based on the classical Legendre polynomial system is incorporated in the adaptive determination of the score generating function, and the proposed sequential procedure is based on a suitably posed stopping rule. Various properties of this sequentailly adaptive procedure and the allied stopping rule are studied. Asymptotic linearity results ( in a shift or regression parameter ) of linear rank statistics are studied with special reference to the Legendre polynomial system and some improved rates of convergence are estabilished in this context.

Keywords:

• Adaptive rank (test) statistics and estimators
• asymtotically optimal score generating function
• contiguity
• Fisher's information
• Legendre polynomial system
• linear rank statistics
• orthonormal system
• rank (R–) estimators
• sequential estimation
• stopping rule