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Laws of Large Numbers for Hilbert Space-Valued Mixingales with Applications

Published online by Cambridge University Press:  11 February 2009

Xiaohong Chen
Affiliation:
University of Chicago
Halbert White
Affiliation:
University of California, San Diego

Abstract

To obtain consistency results for nonparametric estimators based on stochastic processes relevant in econometrics, we introduce the notions of Hilbert space-valued Lp mixingales and near-epoch dependent arrays, and we prove weak and strong laws of large numbers by using a new exponential inequality for Hilbert (H) space-valued martingale difference arrays. We follow Andrews (1988, Econometric Theory 4, 458–467), Hansen (1991, Econometric Theory 7, 213–221; 1992, Econometric Theory 8, 421–422), Davidson (1993, Statistics and Probability Letters 16,301–304), and de Jong (1995, Econometric Theory 11, 347–358), extending results for H = R and improving memory conditions in certain instances. We give as examples consistency results for series and kernel estimators.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1996

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References

REFERENCES

Andrews, D.W.K. (1988) Laws of large numbers for dependent non-identically distributed random variables. Econometric Theory 4, 458467.CrossRefGoogle Scholar
Azuma, K. (1967) Weighted sums of certain dependent random variables. Tohoku Mathemat-icalJournal 19, 357367.Google Scholar
Burkholder, D.L. (1991) Explorations in martingale theory and its applications. In Dold, A.Eckmann, B., & Takens, F. (eds.), Lecture Notes in Mathematics, pp. 266. New York: Springer-Verlag.Google Scholar
Chen, X. & White, H. (1992a) Weak and Strong Laws of Large Numbers for Hilbert Space-Valued Mixingales. Discussion paper 92-15, UCSD Department of Economics.Google Scholar
Chen, X. & White, H. (1992b) Central Limit and Functional Central Limit Theorems for Hilbert Space-Valued Dependent Processes. Discussion paper 92-35, UCSD Department of Economics.Google Scholar
Chen, X. & White, H. (1992c). Asymptotic Properties of Some Projection-Based Robbins-Monro Procedures in a Hilbert Space. Discussion paper 92-46, UCSD Department of Economics.Google Scholar
Chen, X. & White, H. (1995) Adaptive Nonparametric Learning with Feedback. Mimeo, University of Chicago.Google Scholar
Davidson, J. (1993) An L1-convergence theorem for heterogeneous mixingale arrays with trending moments. Statistics and Probability Letters 16, 301304.CrossRefGoogle Scholar
Davidson, J. (1994) Stochastic Limit Theory. New York: Oxford University Press.CrossRefGoogle Scholar
Dehling, H. (1983) Limit theorems for sums of weakly dependent Banach space valued random variables. Zeitschrift fur Wahrscheinlichkeitstheorie und Verwandete Gebiete 63, 393432.CrossRefGoogle Scholar
de Jong, R.M. (1995) Laws of large numbers for dependent heterogeneous processes. Econometric Theory 11, 347358.CrossRefGoogle Scholar
Devroye, L.P. & Wagner, T.J. (1980) Distribution-free consistency results in nonparametric discrimination and regression function estimation. Annals of Statistics 8, 231239.CrossRefGoogle Scholar
Diestel, J. (1984) Sequences and Series in Banach Spaces. New York: Springer-Verlag.CrossRefGoogle Scholar
Egghe, L. (1984) Stopping Time Techniques for Analysts and Probabilists. Cambridge: Cambridge University Press.CrossRefGoogle Scholar
Gallant, A.R. & White, H. (1988) A Unified Theory of Estimation and Inference for Nonlinear Dynamic Models. New York: Basil Blackwell.Google Scholar
Gyorfi, L. & Masry, E. (1990) The L1 and L2 strong consistency of recursive kernel density estimation from dependent samples. IEEE Transactions on Information Theory 36, 531539.CrossRefGoogle Scholar
Hall, P. & Heyde, C.C. (1980) Martingale Limit Theory and Its Applications. New York: Academic Press.Google Scholar
Hansen, B.E. (1991) Strong laws for dependent heterogeneous processes. Econometric Theory 7, 213221.CrossRefGoogle Scholar
Hansen, B.E. (1992) Erratum: Strong laws for dependent heterogeneous processes. Econometric Theory 8, 421422.Google Scholar
Hansen, L.P. (1982) Large sample properties of generalized method of moments estimators. Econometrica 50, 10291054.CrossRefGoogle Scholar
Kallenberg, O. & Sztencel, R. (1991) Some dimension-free features of vector-valued martingales. Probability Theory and Related Fields 88, 215247.CrossRefGoogle Scholar
Kuan, C.-M. & White, H. (1993) Artificial neural networks: An econometric perspective. Econometric Reviews 13, 191.CrossRefGoogle Scholar
Kuan, C.-M. & White, H. (1994) Adaptive learning with nonlinear dynamics driven by dependent processes. Econometrica 62, 10871114.CrossRefGoogle Scholar
McLeish, D.L. (1975) A maximal inequality and dependent strong laws. Annals of Probability 3. 829839.Google Scholar
Nadaraja, E. (1964) On regression estimators. Theory of Probability and Its Applications 9, 157159.Google Scholar
Revesz, P. (1973) Robbins-Monro procedure in a Hilbert space and its application in the theory of learning processes I. Studia Scientiarum Mathematicarum Hungarica 8, 391398.Google Scholar
Robbins, H. & Monro, S. (1951) A stochastic approximation method. Annals of Mathematical Statistics 22, 400407.CrossRefGoogle Scholar
Rosenblatt, M. (1956) Remarks on some nonparametric estimates of a density function. Annals of Mathematical Statistics 27, 832837.CrossRefGoogle Scholar
Venter, J. (1966) On Dvoretzky stochastic approximation theorems. Annals of Mathematical Statistics 37, 15341544.CrossRefGoogle Scholar
Watson, G.S. (1964) Smooth regression analysis. Sankhya 26, 359372.Google Scholar
Wolverton, C.T. & Wagner, T.J. (1969) Asymptotically optimal discriminant functions for pattern classification. IEEE Transactions on Information Theory IT-15, 258265.Google Scholar
Yamato, H. (1971) Sequential estimation of a continuous probability density function and mode. Bulletin of Mathematical Statistics 14, 112.CrossRefGoogle Scholar