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1.
设(Xi,Yi)1≤i≤n为来自二元总体(X,Y)的平稳,φ-混合样本,记m(x)△E(Y│X=x),m(x)的一种递推型核估计为mn(x)=n∑i=1hi^-1Yik((x-Xi)/hi)/n∑j=1h^-1jk(x-Xj)/hj)。本文在一定的条件下证明了(n/(n∑j=1h^-1j)^1/2)(mn(x1)-m(x1),mn(x2)-m(x2),...mn(xr0)-m(xr0))′依分布收  相似文献   

2.
考虑相依回归(SUR)模型yi=Xiβi_ei,i=1,2,…,m,Eei=0,i,j=1;2,…m,其中yi和ei是n×1维随机向量,Xi是n×pi已知矩阵,βi是pi×1维参数向量,∑=(σij)m×m>0.文中给出了两个概念:独立贡献和简洁估计.主要结果是如下五种叙述等价:(1)SUR模型具有独立贡献;(2)βi的BLUE是简洁估计;(3)协方差改进估计是BLUEZ(4)βi的BLUE具有形式其中,j=1,2,…,m;(5)PkNiNj=0,i≠j,k,I,j=1,2,…,m  相似文献   

3.
李学超 《应用数学》1995,8(1):56-59
本文证明了下面的定理:若超图H=(X;E1,E2,...Em)中存在浓度为K长为m的圈,则有m∑i=1(│Ei│-k)>n-k。  相似文献   

4.
本文首先讨论了广义线性模型Y=Xβ+ε(ε~(O,V))的系数β的最优线性无偏估计是用T2=XY作为伴随变量对最小二乘估计T1=(XX)-1X1Y进行改进而得到的协方差改进估计.并把所得结果用于经济领域中的线性相依回归方程系统(SeeminglyUnrelatedRegressionEqautionsSystem).然后关于一类线性相依混合效应回归方程系统,提出了一种优化估计方法。  相似文献   

5.
对于相依线性回归方程组Yi=Xiβi+εi(i=1,2),我们提出了系数向量βi的一种较为简便的“朴实”的两步估计量,例如β1的估计量为β1(T)=(X’1,X1)^-1X‘1Y1-σ12σ22(X’1X1)^-1X‘1TY2。其中Σ=(σij)的一种估计量,本文给出了Σ的一种新取法,通过均方误差矩阵的大小我们证明了这种简便两种估计有有限样本量下可优效于LS估计。  相似文献   

6.
薛留根 《数学杂志》1994,14(4):503-513
设(X1,Y1),…,(Xn,Yn)是从取值于R^p×R^q的随机向量(X,Y)中抽取的随机样本,在给定X=x的条件下Y具有条件密度f(y│x)。在本文中,我们考虑f(y│x)的通常的和递归形式的双重核估计fn(y│x)=n∑i=1K1(Xi-x/an)K2(Yi-6/bn)/〔bn^qn∑j=1K1(Xj-x/an)〕fn(y│x)=n∑i-1K1(Xi-x/ai)K2(Yi-y/bi)/n∑j  相似文献   

7.
REGULARITYANDEXPLICITREPRESENTATIONOF(0,1,…,m-2,m)INTERPOLATIONONTHEZEROSOF(1-x~2)P_(n-2)~(α,β)(x)SHIYINGGUANG(史应光)(ComputingC?..  相似文献   

8.
强相依高斯序列超过数点过程与部分和的联合渐近分布   总被引:7,自引:3,他引:4  
(Xn)为标准化平稳高斯序列,pn=EX1Xn+1,Nn为X1,X2,…,Xn对水平un=x/an+bn的超过数形成的点过程,Mn^(k)为X1,X2,…,Xn的第k个最大值,Sn=(n)∑(i=1)Xi,pnlogn→r∈(0,∞)时,得到Nn与Sn、Mn^(k)与Sn的联合渐近分布。  相似文献   

9.
设X1,...,Xn是一组独立的随机变量序列,设EXi=0,VarZi=μ2,i=1,2,...,n,其中μ2是待估参数,当Xi,i=1,2,...n给定后,分别用Dn=n∑i=1Vi(Xi-X)^2-1/nn∑i=1(Xi-X)^2及Un=n∑i=1(Xi-X)^2及Un=n∑i=1Vi(Xi-n∑i=1ViXi)^2-1/nn∑i-1(Xi-X)^2两种形式的随机加权分布来逼近Tn=1/nn∑  相似文献   

10.
设Xij,i=1,…,mlj=1…,n是任决一个随机变量阵列,令S(i1,j1;i2,j2)∑i=1,∑j=1Xij,M(i1,j1;i2,j2)maxijz≤i≤i2,j1≤j≤j2‖S(i1,j1;i,j)‖1≤i1≤i2≤m,1≤j1≤j2≤n)本文根据所设E(exp(t,/S(i1,j1;i2j2)/)),E/S(i1,j1;i2,j2)/和P(?S(i1,j1;i2,j2?/≥ i)的界  相似文献   

11.
Abstract The aim of this paper is to investigate the central limit theorems for asymptotically negatively dependent random fields under lower moment conditions or the Lindeberg condition. Results obtained improve a central limit theorem of Roussas [11] for negatively assiated fields and the main results of Su and Chi [18], and also include a central limit of theorem for weakly negatively associated random variables similar to that of Burton et al. [20]. Research supported by National Natural Science Foundation of China (No. 19701011)  相似文献   

12.
§ 1  IntroductionWe firstintroduce some concepts.Random variables X and Y are called negative dependent ( ND) if for any pair ofmonotonically non-decresing functions f and g,Cov{ f( X) ,g( Y) }≤ 0 .Clearly itis equivalenttoP( X≤ x,Y≤ y)≤ P( X≤ x) P( Y≤ y)for all x,y∈R.A random sequence{ Xi,i≥ 1 } is said to be negative quadrant dependent( NQD) if any pairof variables Xi,Xj( i≠j) are ND.A sequence of random variables{ Xi,i≥ 1 } is said to be linear negative quadrand depend…  相似文献   

13.
Let {X i, 1in} be a negatively associated sequence, and let {X* i , 1in} be a sequence of independent random variables such that X* i and X i have the same distribution for each i=1, 2,..., n. It is shown in this paper that Ef( n i=1 X i)Ef( n i=1 X* i ) for any convex function f on R 1 and that Ef(max1kn n i=k X i)Ef(max1kn k i=1 X* i ) for any increasing convex function. Hence, most of the well-known inequalities, such as the Rosenthal maximal inequality and the Kolmogorov exponential inequality, remain true for negatively associated random variables. In particular, the comparison theorem on moment inequalities between negatively associated and independent random variables extends the Hoeffding inequality on the probability bounds for the sum of a random sample without replacement from a finite population.  相似文献   

14.
In this article, we obtain the large deviations and moderate deviations for negatively dependent (ND) and non-identically distributed random variables defined on (-∞, +∞). The results show that for some non-identical random variables, precise large deviations and moderate deviations remain insensitive to negative dependence structure.  相似文献   

15.
In risk management, capital requirements are most often based on risk measurements of the aggregation of individual risks treated as random variables. The dependence structure between such random variables has a strong impact on the behavior of the aggregate loss. One finds an extensive literature on the study of the sum of comonotonic risks but less, in comparison, has been done regarding the sum of counter-monotonic risks. A crucial result for comonotonic risks is that the Value-at-risk and the Tail Value-at-risk of their sum correspond respectively to the sum of the Value-at-risk and Tail Value-at-risk of the individual risks. In this paper, our main objective is to derive such simple results for the sum of counter-monotonic risks. To do so, we examine separately different contexts in the class of bivariate strictly continuous distributions for which we obtain closed-form expressions for the Value-at-risk and Tail Value-at-risk of the sum of two counter-monotonic risks. The expressions for the subadditive Tail Value-at risk allow us to quantify the maximal diversification benefit. Also, our findings allow us to analyze the tail of the distribution of the sum of two identically subexponentially distributed counter-monotonic random variables.  相似文献   

16.
§ 1  IntroductionA finite family of random variables { Xi,1≤ i≤ n} is said to be negatively associated(NA) is for every pair of disjointsubsets A1 and A2 of{ 1 ,2 ,...,n} ,Cov{ f1 (Xi,i∈ A1 ) ,f2 (Xj,j∈ A2 ) }≤ 0 ,(1 .1 )whenever f1 and f2 are coordinatewise increasing and the covariance exists.An infinitefamily is negatively associated ifevery finite subfamily is negatively associated.This defini-tion was introduced by Alam and Saxena[1 ] and Joag-Dev and Proschan[2 ] .As pointed…  相似文献   

17.
In this paper, we establish an exact asymptotic formula for the finite-time ruin probability of a nonstandard compound renewal risk model with constant force of interest in which claims arrive in groups, their sizes in one group are identically distributed but negatively dependent, and the inter-arrival times between groups are negatively dependent too.  相似文献   

18.
19.
提出了一个基于客户到来的泊松过程风险模型,其中不同保单发生实际索赔的概率不同,假设潜在索赔额序列为负相依同分布的重尾随机变量序列,且属于重尾族L∩D族的条件下,得到了有限时间破产概率的渐近表达式.  相似文献   

20.
Summary We provide uniform rates of convergence in the central limit theorem for linear negative quadrant dependent (LNQD) random variables. Let <InlineEquation ID=IE"1"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"2"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"3"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"4"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"5"><EquationSource Format="TEX"><![CDATA[<InlineEquation ID=IE"6"><EquationSource Format="TEX"><![CDATA[$]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>]]></EquationSource></InlineEquation>\{X_{n},\allowbreak n\ge1\}$ be a LNQD sequence of random variables with $EX_{n}=0$, set $S_{n}=\sum_{j=1}^{n}X_{j}$ and $B_{n}^{2}=\Var\, (S_{n})$. We show that \begin{gather*} \sup_{x} \left|P\left(\frac{S_{n}}{B_{n}}<x\right)-\Phi(x)\right|= O\bigg(n^{-\delta/(2+3\delta)}\vee \frac{n^{3\delta^{2}/(4+6\delta)}}{B^{2+\delta}_{n}} \sum_{i=1}^{n} E{|X_{i}|}^{2+\delta}\bigg) \end{gather*} under finite $(2+\delta)$th moment and a power decay rate of covariances. Moreover, by the truncation method, we obtain a Berry--Esseen type estimate for negatively associated (NA) random variables with only finite second moment. As applications, we obtain another convergence rate result in the central limit theorem and precise asymptotics in the law of the iterated logarithm for NA sequences, and also for LNQD sequences.  相似文献   

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