Skip to main content
Log in

Extraction of subsystems “Majorized” by the rademacher system

  • Published:
Mathematical Notes Aims and scope Submit manuscript

Abstract

In this paper it is proved that from any uniformly bounded orthonormal system {f n} n=1 of random variables defined on the probability space (Ω, ε, P), one can extract a subsystem {fni} Emphasis>=1/∞i majorized in distribution by the Rademacher system on [0, 1]. This means that {

$$P\left\{ {\omega \in \Omega :\left| {\sum\limits_{i = 1}^m {a_i f_{n_i } } \left( \omega \right)} \right| > z} \right\} \leqslant C\left| {\left\{ {t \in \left[ {0,1} \right]:\left| {\sum\limits_{i = 1}^m {a_i r_i \left( t \right)} } \right| > \frac{z}{C}} \right\}} \right|.$$

}, whereC>0 is independent of m∈N, ai∈N (i=1,…,m) andz>0.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  1. S. Kaczmarz and H. Steinhaus,Theorie der Orthogonalreihen, Warsaw-Lvov (1935).

  2. C. G. Krein, Yu. I. Petunin, and E. M. Semenov,Interpolation of Linear Operators [in Russian], Nauka, Moscow (1978).

    Google Scholar 

  3. J. Bergh and J. Löfström,Interpolation Spaces. An Introduction, Springer-Verlag, Berlin-Heidelberg-New York (1976).

    MATH  Google Scholar 

  4. S. V. Astashkin, “On the interpolation of subspaces of symmetric spaces generated by the Rademacher system,”Izv. RAEN. Ser. MMMIU 1, No. 1, 18–35 (1997).

    MATH  Google Scholar 

  5. S. V. Astashkin, “Series in the Rademacher system that are “close to”L ,”Funktsional. Anal. i Prilozhen. [Functional Anal. Appl.] (to appear).

  6. S. Montgomery-Smith, “The distribution of Rademacher sums,”Proc. Amer. Math. Soc.,109, No. 2, 517–522 (1990).

    Article  MATH  Google Scholar 

  7. T. Holmstedt, “Interpolation of quasi-normed spaces,”Math. Scand.,26, 177–199 (1970).

    MATH  Google Scholar 

  8. S. J. Szarek, “On the best constants in the Khinchine inequality,”Studia Math.,58, 197–208 (1976).

    MATH  Google Scholar 

  9. N. H. Asmar and S. Montgomery-Smith, “On the distribution of Sidon series,”Ark. Mat.,31, No. 1, 13–26 (1993).

    Article  MATH  Google Scholar 

  10. Ya. B. Rutitskii, “On some classes of measurable functions,”Uspekhi Mat. Nauk [Russian Math. Surveys],20, No. 4, 205–208 (1965).

    Google Scholar 

  11. A. Zygmund,Trigonometric Series, Vol. 1, Cambridge Univ. Press, Cambridge (1959).

    MATH  Google Scholar 

  12. R. Elliott,Stochastic Calculus and Applications, Springer-Verlag, Heidelberg (1983).

    Google Scholar 

  13. J. Jakubowski and S. Kwapien, “On multiplicative systems of functions,”Bull. Acad. Polon. Sci. Ser. Sci. Math.,27, No. 9, 689–694 (1979).

    MATH  Google Scholar 

  14. J. Lindenstrauss and L. Tzafriri,Classical Banach Spaces, Vol. 2, Springer, Berlin (1979).

    MATH  Google Scholar 

  15. V. F. Gaposhkin, “Convergence and limiting theorems for subsequences of random values,”Teor. Veroyatnost. i Primenen. [Theory Probab. Appl.],17, No. 3, 401–423 (1972).

    Google Scholar 

  16. V. F. Gaposhkin, “Gap series and independent functions,”Uspekhi Mat. Nauk [Russian Math. Surveys],21 No. 6, 3–82 (1966).

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Additional information

Translated fromMatematicheskie Zametki, Vol. 65, No. 4, pp. 483–495, April, 1999.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Astashkin, S.V. Extraction of subsystems “Majorized” by the rademacher system. Math Notes 65, 407–417 (1999). https://doi.org/10.1007/BF02675354

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/BF02675354

Key words

Navigation