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1.
Summary The members of the power divergence family of statistics all have an asymptotically equivalent χ2 distribution (Cressie and Read [1]). An asymptotic expansion for the distribution function is derived which shows that the speed of convergence to this asymptotic limit is dependent on λ. Known results for Pearson'sX 2 statistic and the log-likelihood ratio statistic then appear as special cases in a continuum rather than as separate (unrelated) expansions.  相似文献   

2.
Thc main aim of this paper is to use the continuation theorem of coincidence degree theory for studying the existence of periodic solutions to a kind of neutral functional differential equation as follows:(x(t)-^n∑i=1cix(t-ri))″=f(x(t))x′+g(x(t-τ))+p(t).In order to do so, we analyze the structure of the linear difference operator A : C2π→C2π, [Ax](t) =x(t)-∑^ni=1cix(t-ri)to determine some flmdamental properties first, which we are going to use throughout this paper. Meanwhile, we also prove some new inequalities which are useful for estimating a priori bounds of periodie solutions.  相似文献   

3.
This paper is concerned with the divergence points with fast growth orders of the partial quotients in continued fractions. Let S be a nonempty interval. We are interested in the size of the set of divergence points
$ E_\varphi (S) = \left\{ {x \in [0,1):{\rm A}\left( {\frac{1} {{\varphi (n)}}\sum\limits_{k = 1}^n {\log a_k (x)} } \right)_{n = 1}^\infty = S} \right\}, $ E_\varphi (S) = \left\{ {x \in [0,1):{\rm A}\left( {\frac{1} {{\varphi (n)}}\sum\limits_{k = 1}^n {\log a_k (x)} } \right)_{n = 1}^\infty = S} \right\},   相似文献   

4.
We present an equivalent definition of functions analytic in the half-plane ℂ+ = {z: Re z > 0} for which
. Translated from Ukrains'kyi Matematychnyi Zhurnal, Vol. 60, No. 9, pp. 1270–1274, September, 2008.  相似文献   

5.
Suppose z 1, z 2, ... z n are complex numbers with absolute values more than 1 and Arg z j Arg z k for j k where Arg w stands for the argument of the complex number w in [0,2). In this note we show that
We also give necessary and sufficient conditions for equality in the above inequality. As an application, we improve the result of Govil and Labelle on Bernstein's inequality for some special polynomials.  相似文献   

6.
For positive integersn, m and realp≥1, let Upper and lower bounds for this quantity are derived, extending results of Brown and Spencer forB 1(n,n), corresponding to the Gale-Berlekamp switching problem. For a Minkowski spaceM of dimensionm, define a quantity investigated by Dvoretzky and Rogers.  相似文献   

7.
We prove a general theorem on the zeros of a class of generalised Dirichlet series. We quote the following results as samples. Theorem A.Let 0<θ<1/2and let {a n }be a sequence of complex numbers satisfying the inequality for N = 1,2,3,…,also for n = 1,2,3,…let α n be real andn| ≤ C(θ)where C(θ) > 0is a certain (small)constant depending only on θ. Then the number of zeros of the function in the rectangle (1/2-δ⩽σ⩽1/2+δ,Tt⩽2T) (where 0<δ<1/2)isC(θ,δ)T logT where C(θ,δ)is a positive constant independent of T provided TT 0(θ,δ)a large positive constant. Theorem B.In the above theorem we can relax the condition on a n to and |aN| ≤ (1/2-θ)-1.Then the lower bound for the number of zeros in (σ⩾1/3−δ,Tt⩽2T)is > C(θ,δ) Tlog T(log logT)-1.The upper bound for the number of zeros in σ⩾1/3+δ,Tt⩽2T) isO(T)provided for every ε > 0. Dedicated to the memory of Professor K G Ramanathan  相似文献   

8.
The paper suggests some conditions on the lower order terms, which provide that the solution of the Dirichlet problem for the general elliptic equation of the second order
$ \begin{gathered} - \sum\limits_{i,j = 1}^n {\left( {a_{i j} \left( x \right)u_{x_i } } \right)_{x_j } + } \sum\limits_{i = 1}^n {b_i \left( x \right)u_{x_i } - } \sum\limits_{i = 1}^n {\left( {c_i \left( x \right)u} \right)_{x_i } + d\left( x \right)u = f\left( x \right) - divF\left( x \right), x \in Q,} \hfill \\ \left. u \right|_{\partial Q} = u_0 \in L_2 \left( {\partial Q} \right) \hfill \\ \end{gathered} $ \begin{gathered} - \sum\limits_{i,j = 1}^n {\left( {a_{i j} \left( x \right)u_{x_i } } \right)_{x_j } + } \sum\limits_{i = 1}^n {b_i \left( x \right)u_{x_i } - } \sum\limits_{i = 1}^n {\left( {c_i \left( x \right)u} \right)_{x_i } + d\left( x \right)u = f\left( x \right) - divF\left( x \right), x \in Q,} \hfill \\ \left. u \right|_{\partial Q} = u_0 \in L_2 \left( {\partial Q} \right) \hfill \\ \end{gathered}   相似文献   

9.
Multilinear Singular Integrals with Rough Kernel   总被引:9,自引:0,他引:9  
For a class of multilinear singular integral operators T A ,
where R m (A; x, y) denotes the m-th Taylor series remainder of A at x expanded about y, A has derivatives of order m − 1 in is homogeneous of degree zero, the authors prove that T A is bounded from L p (ℝ n ) to and from L 1(ℝ n ) to L n/(nβ),∞(ℝ n ) with the bound And if Ω has vanishing moments of order m − 1 and satisfies some kinds of Dini regularity otherwise, then T A is also bounded from L p (ℝ n ) to with the bound Supported by the National 973 Project (G1990751) and SEDF of China (20010027002)  相似文献   

10.
Let X 1, X 2, ... be i.i.d. random variables. The sample range is R n = max {X i , 1 ≤ i ≤ n} − min {X i , 1 ≤ i ≤ n}. If for a non-degenerate distribution G and some sequences (α k ), (β k ) then we have
and
almost surely for any continuity point x of G and for any bounded Lipschitz function f: R → R.   相似文献   

11.
Riassunto In questo lavoro si prova la regolarità h?lderiana delle derivate, fino all'ordinek, dei minimi locali dei funzionali sotto opportune ipotesi suA ij αβ e sug.
Summary In this paper we prove h?lder-continuity of the derivates, up to orderk, of local minima of functionals under suitable hypotheses forA ij αβ andg.
  相似文献   

12.
Summary LetX=(X n; n≧0,X 0=1) be a supercritical Galton-Watson process. The limiting distribution of ) where is the m.l.e. of the offspring mean, is derived. As an application of this result, some limit theorems leading ultimately to a parameter free result of statistical interest, are also established.  相似文献   

13.
Periodicity in a Nonlinear Predator-prey System with State Dependent Delays   总被引:1,自引:0,他引:1  
With the help of a continuation theorem based on Gaines and Mawhin's coincidence degree, easily verifiable criteria are established for the global existence of positive periodic solutions of the following nonlinear state dependent delays predator-prey system where a_i(t),c_j(t),d_i(t) are continuous positive periodic functions with periodic ω>0, b_1(t),b_2(t) are continuous periodic functions with periodic ωand ∫_0~ωbi(t)dt>0. T_i,σ_j, p_i (i=1,2,…,n, j=1, 2,…,m) are continuous and ω-periodic with respect to their first arguments, respectively, α_i, β_j,γ_i(i=1,2,…,n, j=1,2, …, m) are positive constants.  相似文献   

14.
Suppose that X is a complex Banach space with the norm ‖·‖ and n is a positive integer with dim Xn ⩾ 2. In this paper, we consider the generalized Roper-Suffridge extension operator $ \Phi _{n,\beta _2 ,\gamma _2 , \ldots ,\beta _{n + 1} ,\gamma _{n + 1} } (f) $ \Phi _{n,\beta _2 ,\gamma _2 , \ldots ,\beta _{n + 1} ,\gamma _{n + 1} } (f) on the domain $ \Omega _{p_1 ,p_2 , \ldots ,p_{n + 1} } $ \Omega _{p_1 ,p_2 , \ldots ,p_{n + 1} } defined by
$ \Phi _{n,\beta _2 ,\gamma _2 , \ldots ,\beta _{n + 1} ,\gamma _{n + 1} } (f)(x) = {*{20}c} {\sum\limits_{j = 1}^n {\left( {\frac{{f(x_1^* (x))}} {{x_1^* (x)}}} \right)} ^{\beta _j } (f'(x_1^* (x)))^{\gamma _j } x_1^* (x)x_j } \\ { + \left( {\frac{{f(x_1^* (x))}} {{x_1^* (x)}}} \right)^{\beta _{n + 1} } (f'(x_1^* (x)))^{\gamma _{n + 1} } \left( {x - \sum\limits_{j = 1}^n {x_1^* (x)x_j } } \right)} \\ $ \Phi _{n,\beta _2 ,\gamma _2 , \ldots ,\beta _{n + 1} ,\gamma _{n + 1} } (f)(x) = \begin{array}{*{20}c} {\sum\limits_{j = 1}^n {\left( {\frac{{f(x_1^* (x))}} {{x_1^* (x)}}} \right)} ^{\beta _j } (f'(x_1^* (x)))^{\gamma _j } x_1^* (x)x_j } \\ { + \left( {\frac{{f(x_1^* (x))}} {{x_1^* (x)}}} \right)^{\beta _{n + 1} } (f'(x_1^* (x)))^{\gamma _{n + 1} } \left( {x - \sum\limits_{j = 1}^n {x_1^* (x)x_j } } \right)} \\ \end{array}   相似文献   

15.
In this paper, we obtain positive solution to the following multi-point singular boundary value problem with p-Laplacian operator,{( φp(u'))'+q(t)f(t,u,u')=0,0〈t〈1,u(0)=∑i=1^nαiu(ξi),u'(1)=∑i=1^nβiu'(ξi),whereφp(s)=|s|^p-2s,p≥2;ξi∈(0,1)(i=1,2,…,n),0≤αi,βi〈1(i=1,2,…n),0≤∑i=1^nαi,∑i=1^nβi〈1,and q(t) may be singular at t=0,1,f(t,u,u')may be singular at u'=0  相似文献   

16.
The following boundary value problem is studied:
here the surface Г satisfies the condition( , where
and ν is the outward (with respect to Ω) normal to Γ. Translated fromMatematischskie Zametki, Vol. 61, No. 5, pp. 759–768, May, 1997. Translated by N. K. Kulman  相似文献   

17.
Abstract   The singular second-order m-point boundary value problem
, is considered under some conditions concerning the first eigenvalue of the relevant linear operators, where ()(x) = (p(x)ϕ′(x))′ + q(x)ϕ(x) and ξ i ∈ (0, 1) with 0 < ξ1 < ξ2 < · · · < ξ m−2 < 1, a i ∈ [0, ∞). h(x) is allowed to be singular at x = 0 and x = 1. The existence of positive solutions is obtained by means of fixed point index theory. Similar conclusions hold for some other m-point boundary value conditions. Supported by the National Natural Science Foundation of China (No.10371066, No.10371013)  相似文献   

18.
Approximation to the function |x| plays an important role in approximation theory. This paper studies the approximation to the function xαsgn x, which equals |x| if α = 1. We construct a Newman Type Operator rn(x) and prove max |x|≤1|xαsgn x-rn(x)|~Cn1/4e-π1/2(1/2)αn.  相似文献   

19.
A Supplement to the Baum-Katz-Spitzer Complete Convergence Theorem   总被引:1,自引:0,他引:1  
Let {X, Xn; n≥ 1} be a sequence of i.i.d. Banach space valued random variables and let {an; n ≥ 1} be a sequence of positive constants such that an↑∞ and 1〈 lim inf n→∞ a2n/an≤lim sup n→∞ a2n/an〈∞ Set Sn=∑i=1^n Xi,n≥1.In this paper we prove that ∑n≥1 1/n P(||Sn||≥εan)〈∞ for all ε〉0 if and only if lim n→∞ Sn/an=0 a.s. This result generalizes the Baum-Katz-Spitzer complete convergence theorem. Combining our result and a corollary of Einmahl and Li, we solve a conjecture posed by Gut.  相似文献   

20.
Let Un be the unit polydisc of Cn and φ= (φ1,...,φn? a holomorphic self-map of Un. Let 0≤α< 1. This paper shows that the composition operator Cφ, is bounded on the Lipschitz space Lipa(Un) if and only if there exists M > 0 such thatfor z∈Un. Moreover Cφ is compact on Lipa(Un) if and only if Cφ is bounded on Lipa(Un) and for every ε > 0, there exists a δ > 0 such that whenever dist(φ(z),σUn) <δ  相似文献   

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