Abstract
The problem to establish the asymptotic distribution of statistical estimators as well as the moment convergence of such estimators has been recognized as an important issue in advanced theories of statistics. This problem has been deeply studied for M-estimators for a wide range of models by many authors. The purpose of this paper is to present an alternative and apparently simple theory to derive the moment convergence of Z-estimators. In the proposed approach the cases of parameters with different rate of convergence can be treated easily and smoothly and any large deviation type inequalities necessary for the same result for M-estimators do not appear in this approach. Applications to the model of i.i.d. observation, Cox’s regression model as well as some diffusion process are discussed.
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References
Andersen PK, Gill RD (1982) Cox’s regression models for counting processes: a large sample study. Ann Stat 10:1100–1120
Cox DR (1972) Regression models and life-tables (with discussion). J R Stat Soc B 34:187–220
Ibragimov IA, Has’minskii RZ (1981) Statistical estimation: asymptotic theory. Springer, New York
Kallenberg O (2002) Foundations of modern probability, 2nd edn. Springer, New York
Kato K (2011) A note on moment convergence of bootstrap \(M\)-estimators. Stat Decis 28:51–61
Kessler M (1997) Estimation of an ergodic diffusion from discrete observations. Scand J Stat 24:211–229
Kutoyants YA (1984) Parameter estimation for stochastic processes. Heldermann, Berlin
Kutoyants YA (1994) Identification of dynamical systems with small noise. Kluwer Academic Publishers, Dordrecht
Kutoyants YuA (2004) Statistical inference for ergodic diffusion processes. Springer, London
Nishiyama Y (2010) Moment convergence of \(M\)-estimators. Stat Neerl 64:505–507
Uchida M, Yoshida N (2012) Adaptive estimation of an ergodic diffusion process based on sampled data. Stoch Process Appl 122:2885–2924
Uchida M, Yoshida N (2013) Quasi likelihood analysis of volatility and nondegeneracy of statistical random field. Stoch Process Appl 123:2851–2876
van der Vaart AW (1998) Asymptotic statistics. Cambridge University Press, Cambridge
van der Vaart AW, Wellner JA (1996) Weak convergence and empirical processes: with applications to statistics. Springer, New York
Yoshida N (2011) Polynomial type large deviation inequalities and quasi-likelihood analysis for stochastic differential equations. Ann Inst Stat Math 63:431–479
Acknowledgments
The authors thank an anonymous referee for her or his helpful comments. This work was supported by Italian MIUR, Grant 2009 (I.N.) and by Grant-in-Aid for Scientific Research (C), 24540152, from Japan Society for the Promotion of Science (Y.N.).
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Negri, I., Nishiyama, Y. Moment convergence of Z-estimators. Stat Inference Stoch Process 20, 387–397 (2017). https://doi.org/10.1007/s11203-016-9146-0
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DOI: https://doi.org/10.1007/s11203-016-9146-0