Abstract
We consider a sequence of general filtered statistical models with a finite-dimensional parameter. It is tacitly assumed that a proper rescaling of the parameter space is already done (so we deal with a local parameter) and also time rescaling is done if necessary. Our first and main purpose is to give sufficient conditions for the existence of certain uniform in time linear–quadratic approximations of log-likelihood ratio processes. Second, we prove general theorems establishing LAN, LAMN and LAQ properties for these models based on these linear–quadratic approximations. Our third purpose is to prove three theorems related to the necessity of the conditions in our main result. These theorems assert that these conditions are necessarily satisfied if (1) an approximation of a much more general form exists and a (necessary) condition of asymptotic negligibility of jumps of likelihood ratio processes holds, or (2) we have LAN property at every moment of time and the limiting models are continuous in time, or (3) we have LAN property, Hellinger processes are asymptotically degenerate at the terminal times, and the condition of asymptotic negligibility of jumps holds.
Esko Valkeila—Deceased
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Notes
- 1.
To be more precise, approximations and limits are assumed to be uniform on all compact parameter subsets. The corresponding properties are often called ULAN (uniform LAN), ULAMN, etc. However, we omit the letter ‘U’ in the notation.
References
Fabian, V., Hannan, J.: Local asymptotic behavior of densities. Stat. Decis. 5, 105–138 (1987)
Greenwood, P.E., Shiryayev, A.N.: Contiguity and the Statistical Invariance Principle. Gordon and Breach, New York (1985)
Gushchin, A.A.: On taking limits under the compensator sign. In: Ibragimov, I.A., Zaitsev, A.Yu. (eds.) Probability Theory and Mathematical Statistics (St. Petersburg 1993), pp. 185–192. Gordon and Breach, Amsterdam (1996)
Gushchin, A.A., Küchler, U.: Asymptotic inference for a linear stochastic differential equation with time delay. Bernoulli 5, 1059–1098 (1999)
Gushchin, A.A., Valkeila, E.: Exponential approximation of statistical experiments. In: Balakrishnan, N., et al. (eds.) Asymptotic Methods in Probability and Statistics with Applications (St. Petersburg 1998), pp. 409–423. Birkhäuser, Boston (2001)
Gushchin, A.A., Valkeila, E.: Approximations and limit theorems for likelihood ratio processes in the binary case. Stat. Decis. 21, 219–260 (2003)
Hallin, M., Van Den Akker, R., Werker, B.J.: On quadratic expansions of log-likelihoods and a general asymptotic linearity result. In: Hallin, M., et al. (eds.) Mathematical Statistics and Limit Theorems, pp. 147–165. Springer, Cham (2015)
Höpfner, R.: Asymptotic inference for continuous-time Markov chains. Probab. Theory Relat. Fields 77, 537–550 (1988)
Höpfner, R.: On statistics of Markov step processes: representation of log-likelihood ratio processes in filtered local models. Probab. Theory Relat. Fields 94, 375–398 (1988)
Höpfner, R.: Asymptotic Statistics. Walter de Gruyter, Berlin (2014)
Höpfner, R., Jacod, J.: Some remarks on the joint estimation of the index and the scale parameter for stable processes. In: Mandl, P., Hušková, M. (eds.) Asymptotic Statistics: Proceedings of the 5th Prague Symposium 1993, pp. 273–284. Physica Verlag, Heidelberg (1994)
Jacod, J.: Calcul Stochastique et Problèmes de Martingales. Lecture Notes in Mathematics, vol. 714. Springer, Berlin (1979)
Jacod, J.: Filtered statistical models and Hellinger processes. Stoch. Process. Appl. 32, 3–45 (1989)
Jacod, J.: Convergence of filtered statistical models and Hellinger processes. Stoch. Process. Appl. 32, 47–68 (1989)
Jacod, J.: Une application de la topologie d’Emery: le processus information d’un modèle statistique filtré. Séminaire de Probabilités XXIII. Lecture Notes in Mathematics, vol. 1372, pp. 448–474. Springer, Berlin (1989)
Jacod, J., Shiryaev, A.N.: Limit Theorems for Stochastic Processes, 2nd edn. Springer, Berlin (2003)
Janssen, A.: Limits of translation invariant experiments. J. Multivar. Anal. 20, 129–142 (1986)
Janssen, A.: Asymptotically linear and mixed normal sequences of statistical experiments. Sankhya: Ser. A 53, 1–26 (1991)
Janssen, A.: Asymptotic relative efficiency of tests at the boundary of regular statistical models. J. Stat. Plan. Inference 126, 461–477 (2004)
Kallenberg, O.: Foundations of Modern Probability, 2nd edn. Springer, New York (2002)
Kutoyants, Yu.: Identification of Dynamical Systems with Small Noise. Kluwer, Dordrecht (1994)
Le Cam, L.: Locally asymptotically normal families of distributions. Univ. Calif. Publ. Stat. 3, 37–98 (1960)
Le Cam, L.: Likelihood functions for large numbers of independent observations. In: David, F.N. (ed.) Research Papers in Statistics (Festschrift J. Neyman), pp. 167–187. Wiley, London (1966)
Le Cam, L.: Sur l’approximation de familles de mesures par des familles gaussiennes. Annales de l’I.H.P. Probabilités et statistiques 21, 225–287 (1985)
Le Cam, L.: Asymptotic Methods in Statistical Decision Theory. Springer, New York (1986)
Le Cam, L., Yang, G.L.: On the preservation of local asymptotic normality under information loss. Ann. Stat. 16, 483–520 (1988)
Le Cam, L., Yang, G.L.: Asymptotics in Statistics: Some Basic Concepts, 2nd edn. Springer, New York (2000)
Lin’kov, Yu.N.: Asymptotic Statistical Methods for Stochastic Processes. Translations of Mathematical Monographs, vol. 196. American Mathematical Society, Providence (2001) Russian original: Kiev, Naukova Dumka (1993)
Liptser, R.Sh, Shiryayev, A.N.: Theory of Martingales. Kluwer, Dordrecht (1989)
Liptser, R.S., Shiryaev, A.N.: Statistics of Random Processes. I. General Theory, 2nd edn. Springer, Berlin (2001)
Luschgy, H.: Local asymptotic mixed normality for semimartingale experiments. Probab. Theory Relat. Fields 92, 151–176 (1992)
Luschgy, H.: Asymptotic inference for semimartingale models with singular parameter points. J. Stat. Plan. Inference 39, 155–186 (1994)
Luschgy, H.: Local asymptotic quadraticity of stochastic process models based on stopping times. Stoch. Process. Appl. 57, 305–317 (1995)
Pfanzagl, J.: On distinguished LAN-representations. Math. Methods Stat. 11, 477–488 (2002)
Shiryaev, A.N., Spokoiny, V.G.: Statistical Experiments and Decisions: Asymptotic Theory. World Scientific, Singapore (2000)
Strasser, H.: Scale invariance of statistical experiments. Probab. Math. Stat. 5, 1–20 (1985)
Strasser, H.: Stability of filtered experiments. In: Sendler, W. (ed.) Contributions to Stochastics, pp. 202–213. Physica Verlag, Heidelberg (1987)
Vostrikova, L.: Functional limit theorems for the likelihood ratio processes. Ann. Univ. Sci. Budapest. Sect. Comput. 6, 145–182 (1985)
Vostrikova, L.: On the weak convergence of likelihood ratio processes of general statistical parametric models. Stochastics 23, 277–298 (1988)
Acknowledgements
This research was supported by Suomalainen Tiedeakatemia (A.A. Gushchin), by Academy of Finland grants 210465 and 212875 (E. Valkeila), and by the program Tête-à -tête in Russia (Euler International Mathematical Institute; both authors). For the first author, this work has been funded by the Russian Academic Excellence Project ‘5-100’. The first author is deeply grateful to the referees for a number of comments aimed at improving the exposition.
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Gushchin, A., Valkeila, E. (2017). Quadratic Approximation for Log-Likelihood Ratio Processes. In: Panov, V. (eds) Modern Problems of Stochastic Analysis and Statistics. MPSAS 2016. Springer Proceedings in Mathematics & Statistics, vol 208. Springer, Cham. https://doi.org/10.1007/978-3-319-65313-6_8
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