Abstract
We construct a stationary Markov process with trivial tail σ-field and a nondegenerate observation process such that the corresponding nonlinear filtering process is not uniquely ergodic. This settles in the negative a conjecture of the author in the ergodic theory of nonlinear filters arising from an erroneous proof in the classic paper of H. Kunita (1971), wherein an exchange of intersection and supremum of σ-fields is taken for granted.
Similar content being viewed by others
References
P. Baxendale, P. Chigansky and R. Liptser, Asymptotic stability of the Wonham filter: ergodic and nonergodic signals, SIAM Journal on Control and Optimiziation 43 (2004), 643–669.
J. Brossard and C. Leuridan, Chaînes de Markov constructives indexées par Z, The Annals of Probability 35 (2007), 715–731.
A. Budhiraja, Asymptotic stability, ergodicity and other asymptotic properties of the nonlinear filter, Annales de l’Institut Henri Poincaré. Probabilités et Statistiques 39 (2003), 919–941.
O. Cappé, E. Moulines and T. Rydén, Inference in Hidden Markov Models, Springer Series in Statistics, Springer, New York, 2005.
L. Chaumont and M. Yor, Exercises in Probability, Cambridge University Press, Cambridge, 2003.
P. Chigansky and R. van Handel, A complete solution to Blackwell’s unique ergodicity problem for hidden Markov chains, The Annals of Applied Probability 20 (2010), 2318–2345.
I. Crimaldi, G. Letta and L. Pratelli, Sur l’interversion de l’ordre entre deux opérations sur les tribus, Comptes Rendus Mathématique. Académie des Sciences. Paris 345 (2007), 341–344.
F. den Hollander and J. E. Steif, Random walk in random scenery: a survey of some recent results, in Dynamics & Stochastics, IMS Lecture Notes Monograph Series, Vol. 48, Institute of Mathematical Statistics, Beachwood, OH, 2006, pp. 53–65.
M. Émery and W. Schachermayer, On Vershik’s standardness criterion and Tsirelson’s notion of cosiness, Séminaire de Probabilités, XXXV, Lecture Notes in Mathematics, Vol. 1755, Springer, Berlin, 2001, pp. 265–305.
S. A. Kalikow, T, T −1 transformation is not loosely Bernoulli, Annals of Mathematics 115 (1982), 393–409.
H. Kesten, Distinguishing and reconstructing sceneries from observations along random walk paths, in Microsurveys in Discrete Probability (Princeton, NJ, 1997), DIMACS Ser. Discrete Math. Theoret. Comput. Sci., Vol. 41, American Mathematical Society, Providence, RI, 1998, pp. 75–83.
H. Kunita, Asymptotic behavior of the nonlinear filtering errors of Markov processes, Journal of Multivariate Analysis 1 (1971), 365–393.
S. Laurent, Further comments on the representation problem for stationary processes, Statistics & Probability Letters 80 (2010), 592–596.
A. J. Majda, J. Harlim and B. Gershgorin, Mathematical strategies for filtering turbulent dynamical systems, Discrete and Continuous Dynamical Systems 27 (2010), 441–486.
P. Masani, Wiener’s contributions to generalized harmonic analysis, prediction theory and filter theory, American Mathematical Society. Bulletin 72 (1966), 73–125.
H. Matzinger and S. W. W. Rolles, Reconstructing a random scenery observed with random errors along a random walk path, Probability Theory and Related Fields 125 (2003), 539–577.
I. Meilijson, Mixing properties of a class of skew-products, Israel Journal of Mathematics 19 (1974), 266–270.
P. A. Meyer, La théorie de la prédiction de F. Knight, in Séminaire de Probabilités, X (Premi`ere partie, Univ. Strasbourg, Strasbourg, année universitaire 1974/1975), Lecture Notes in Mathematics, Vol. 511, Springer, Berlin, 1976, pp. 86–103.
S. Meyn and R. L. Tweedie, Markov Chains and Stochastic Stability, second edition, Cambridge University Press, Cambridge, 2009.
D. S. Ornstein, An application of ergodic theory to probability theory, The Annals of Probability 1 (1973), 43–65.
M. Rahe, Relatively finitely determined implies relatively very weak Bernoulli, Canadian Journal of Mathematics 30 (1978), 531–548.
Ya. G. Sinai, Kolmogorov’s work on ergodic theory, The Annals of Probability 17 (1989), 833–839.
M. Smorodinsky, Ergodic Theory, Entropy, Lecture Notes in Mathematics, Vol. 214, Springer-Verlag, Berlin, 1971.
H. Totoki, On a class of special flows, Zeitschrift für Wahrscheinlichkeitstheorie und Verwandte Gebiete 15 (1970), 157–167.
R. van Handel, The stability of conditional Markov processes and Markov chains in random environments, The Annals of Probability 37 (2009), 1876–1925.
R. van Handel, Uniform time average consistency of Monte Carlo particle filters, Stochastic Processes and their Applications 119 (2009), 3835–3861.
R. van Handel, When do nonlinear filters achieve maximal accuracy? SIAM Journal on Control and Optimization 48 (2009/10), 3151–3168.
V. A. Volkonskii and Yu. A. Rozanov, Some limit theorems for random functions. I, Theory of Probability and its Applications 4 (1959), 178–197.
H. von Weizsäcker, Exchanging the order of taking suprema and countable intersections of σ-algebras, Annales de l’Institut Henri Poincaré. Section B. Calcul des Probabilités et Statistique. Nouvelle Série 19 (1983), 91–100.
B. Weiss, The isomorphism problem in ergodic theory, American Mathematical Society. Bulletin 78 (1972), 668–684.
D. Williams, Probability with Martingales, Cambridge University Press, 1991.
K. Yano and M. Yor, Around Tsirelson’s equation, or: the evolution process may not explain everything, 2010, preprint, arxiv:0906.3442.
M. Yor, Sur les théories du filtrage et de la prédiction, in Séminaire de Probabilités, XI (Univ. Strasbourg, Strasbourg, 1975/1976), Lecture Notes in Mathematics, Vol. 581, Springer, Berlin, 1977, pp. 257–297.
Author information
Authors and Affiliations
Corresponding author
Additional information
This work was partially supported by NSF grant DMS-1005575.
Rights and permissions
About this article
Cite this article
van Handel, R. On the exchange of intersection and supremum of σ-fields in filtering theory. Isr. J. Math. 192, 763–784 (2012). https://doi.org/10.1007/s11856-012-0045-9
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11856-012-0045-9