TY - JOUR JF - Bernoulli: official journal of the Bernoulli Society for Mathematical Statistics and Probability AV - public SP - 873 TI - Nonlinear Wavelet Estimation of Time-Varying Autoregressive Processes UR - https://archiv.ub.uni-heidelberg.de/volltextserver/21429/ Y1 - 1999/// KW - Nonlinear thresholding; non-stationary processes; time series; time-varying autoregression; wavelet estimators VL - 5 N2 - We consider nonparametric estimation of the coefficients, of atime-varying autoregressive process. Choosing an orthonormal wavelet basisrepresentation of the coefficient functions, the empirical wavelet coefficientsare derived from the time series data as the solution of a least squares minimizationproblem. In order to allow the coefficient functions to be of inhomogeneous regularity,we apply nonlinear thresholding to the empirical coefficients and obtain locally smoothedestimates of the coefficient functions. We show that the resulting estimators attain theusual minimax L_2-rates up to a logarithm factor, simultaneously in a large scale of Besovclasses. ID - heidok21429 A1 - Dahlhaus, Rainer A1 - Neumann, Michael H. A1 - von Sachs, Rainer EP - 906 IS - 5 CY - Aarhus SN - 1350-7265 ER -