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1.
§ 1  Introduction and resultsL et { X,Xi;i≥ 1} be a sequence of i.i.d.random variables,and set Sn= ni=1 Xi,n≥1.Hsu and Robbins[1 ] introduced the conceptof complete convergence.They together withErdos[2 ] proved n≥ 1 P(|Sn|≥εn) <∞ ,ε>0 (1)if and only if EX=0 and EX2 <∞ .L ater,Spitzer[3] proved n≥ 11n P(|Sn|≥εn) <∞ ,ε>0if and only if EX =0 and E|X|<∞ .More generally,it was shown by Baum and Katz[4 ]that,for 0 0 (…  相似文献   

2.
In this paper, we discuss the moving-average process Xk = ∑i=-∞ ^∞ ai+kεi, where {εi;-∞ 〈 i 〈 ∞} is a doubly infinite sequence of identically distributed ψ-mixing or negatively associated random variables with mean zeros and finite variances, {ai;-∞ 〈 i 〈 -∞) is an absolutely solutely summable sequence of real numbers.  相似文献   

3.
Estimates for deviations are established for a large class of linear methods of approximation of periodic functions by linear combinations of moduli of continuity of different orders. These estimates are sharp in the sense of constants in the uniform and integral metrics. In particular, the following assertion concerning approximation by splines is proved: Suppose that is odd, . Then
moreover, for it is impossible to decrease the constants on . Here, are some explicitly constructed constants, is the modulus of continuity of order r for the function f, and are explicitly constructed linear operators with the values in the space of periodic splines of degree of minimal defect with 2n equidistant interpolation points. This assertion implies the sharp Jackson-type inequality
. Bibliography: 17 titles.  相似文献   

4.
In the canonical smooth fiber bundles endowed with the metric tensor fields of relevant structure, we consider natural representations of the Galilean groups and construct -invariant generalizations of differentiable connections. In both regular and special cases of the representations of the relevant groups , we found all the affine nonholonomic -, -, and -connections of the first order (see [1]–[3]) possessing the local Lie groups of transformations and also described the respective -invariant planar connections.  相似文献   

5.
Let, for σ > 0, be the set of complex functions fL 1 (ℝ) with the Fourier transforms vanishing outside the interval [−σ; σ]. In this paper, we study the problem of the best approximation of the Dirac function δ (which has the Fourier transform with widest support supp ) by functions . More precisely, we consider the quantity inf and its extremal functions . __________ Translated from Lietuvos Matematikos Rinkinys, Vol. 46, No. 4, pp. 548–564, October–December, 2006.  相似文献   

6.
7.
In what follows, $C$ is the space of -periodic continuous functions; P is a seminorm defined on C, shift-invariant, and majorized by the uniform norm; is the mth modulus of continuity of a function f with step h and calculated with respect to P; , ( ), ,
,
Theorem 1. Let . Then
For some values of and seminorms related to best approximations by trigonometric polynomials and splines in the uniform and integral metrics, the inequalities are sharp. Bibliography: 6 titles.  相似文献   

8.
In the canonical smooth fiber bundles endowed with the metric tensor fields of relevant structure, we consider natural representations of the Galilean groups (1, n) and construct (1, n)-invariant generalized differential-geometric connections. In both regular and special cases of the representations of the considered groups (1, n), we find all affine nonholonomic , and 1,2-connections of the first order (see [1]–[3]) possessing the local Lie groups of transformations (1, n) and also describe the corresponding (1, n)invariant planar connections.  相似文献   

9.
Absolute continuity of the distribution of some Markov geometric series   总被引:1,自引:0,他引:1  
Let (∈n)≥0 be the Markov chain of two states with respect to the probability measure of the maximal entropy on the subshift space ∑A defined by Fibonacci incident matrix A.We consider the measure μλ of the probability distribution of the random series ∑∞n=0 εnλn (0 <λ< 1).It is proved that μλ is singular if λ∈ (0,√5-1/2) and that μλ is absolutely continuous for almost all λ∈ (√5-1/2,0.739).  相似文献   

10.
The regular solutions of generalized axisymmetric potential equation , a>−1/2 are called generalized axisymmetric potentials. In this paper, the characterizations of lower order and lower type of entire GASP in terms of their approximation error {En} have been obtained.  相似文献   

11.
We give the asymptotics of the sum , where , for the multiplicative functions , and .  相似文献   

12.
We consider the series and whose coefficients satisfy the condition for , where the sequence can be expressed as the union of a finite number of lacunary sequences. The following results are obtained. If as , then the series is uniformly convergent. If for all , then the sequence of partial sums of this series is uniformly bounded. If the series is convergent for and as , then this series is uniformly convergent. If the sequence of partial sums of the series for is bounded and for all , then the sequence of partial sums of this series is uniformly bounded. In these assertions, conditions on the rates of decrease of the coefficients of the series are also necessary if the sequence is lacunary. In the general case, they are not necessary.  相似文献   

13.
We prove a local limit theorem for large deviations of the sums , where , is a Markov Gaussian random field, is a bounded vector-valued function, and . This paper generalizes the paper [13].  相似文献   

14.
15.
Both the clear effects and minimum aberration criteria are the important rules for the design selection. In this paper, it is proved that some designs have weak minimum aberration, by considering the number of clear two-factor interactions in the designs. And some conditions are provided, under which a design can have the maximum number of clear two-factor interactions and weak minimum aberration at the same time. Some weak minimum aberration designs are provided for illustrations and two nonisomorphic weak minimum aberration designs are constructed at the end of this paper.  相似文献   

16.
Suppose that , , and are three discrete probability distributions related by the equation (E): , where denotes the k-fold convolution of In this paper, we investigate the relation between the asymptotic behaviors of and . It turns out that, for wide classes of sequences and , relation (E) implies that , where is the mean of . The main object of this paper is to discuss the rate of convergence in this result. In our main results, we obtain O-estimates and exact asymptotic estimates for the difference .  相似文献   

17.
Let M n = X 1 + ⋯ + X n be a sum of independent random variables such that X k ⩽ 1, and EX k 2 = σ k 2 for all k. Hoeffding [15, Theorem 3] proved that
with
. Bentkus [5] improved Hoeffding’s inequalities using binomial tails as upper bounds. Let and stand for the skewness and kurtosis of X k . In this paper we prove (improved) counterparts of the Hoeffding inequality replacing σ 2 by certain functions of γ 1, ..., γ n (respectively ϰ1, ..., ϰ1). Our bounds extend to a general setting where X k are martingale differences, and they can combine the knowledge of skewness and/or kurtosis and/or variances of X k . Up to factors bounded by e 2/2 the bounds are final. All our results are new since no inequalities incorporating skewness or kurtosis control are known so far. The research was partially supported by the Lithuanian State Science and Studies Foundation, grant No T-15/07.  相似文献   

18.
Yee  Ae Ja 《The Ramanujan Journal》2001,5(3):247-262
A lecture hall partition of length n is an integer sequence satisfying Bousquet-Mélou and Eriksson showed that the number of lecture hall partitions of length n of a positive integer N whose alternating sum is k equals the number of partitions of N into k odd parts less than 2n. We prove the fact by a natural combinatorial bijection. This bijection, though defined differently, is essentially the same as one of the bijections found by Bousquet-Mélou and Eriksson.  相似文献   

19.
In this paper, optimal investment and consumption decisions for an optimal choiceproblem in infinite borizon are considered, for an investor who has available a bank account anda stock whose price is a log normal diffusion. The bank pays at an interest rate r for any de-posit, and takes at a larger rate / for any loan. As in the paper of Xu Wensheng and ChenShuping in JAMS(B), where an analogous problem in finite horizon is studied, optimal strategies are obtained via Hamilton-Jacobi-Bellman (ladE) equation which is derived from dynamic c1-programming principle. For the specific HARA case, i.e. U(t,c)=e^-βtc^1-R/1-R, this paper getsthe optimal consumption and optimal investment in the form of c^‘1 =β -^-g/Rwi and π^‘1= b -- γ / Rσ^2wr, with γ1,=max{γ,min{γ‘,b--Rσ^2‘} },^-g=(1--R)[γ (b-γ)^2/2Rσ^2]. This result coincides with the classical one under condition γ‘ ≡γ.  相似文献   

20.
Dehornoy constructed a right invariant order on the braid group B n uniquely defined by the condition 1{\text{ if }}\beta _0 ,\beta _1$$ " align="middle" border="0"> are words in . A braid is called strongly positive if 1$$ " align="middle" border="0"> for any . In the present paper it is proved that the braid is strongly positive if the word does not contain . We also provide a geometric proof of the result by Burckel and Laver that the standard generators of a braid group are strongly positive. Finally, we discuss relations between the right invariant order and quasipositivity.  相似文献   

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