共查询到20条相似文献,搜索用时 15 毫秒
1.
Chris Field John Robinson Elvezio Ronchetti 《Annals of the Institute of Statistical Mathematics》2008,60(1):225-227
We obtain marginal tail area approximations for the one-dimensional test statistic based on the appropriate component of the
M-estimate for both standardized and Studentized versions which are needed for tests and confidence intervals. The result is
proved under conditions which allow the application to finite sample situations such as the bootstrap and involves a careful
discretization with saddlepoints being used for each neighbourhood. These results are used to obtain second-order relative
error results on the accuracy of the Studentized and the tilted bootstrap. The tail area approximations are applied to a Poisson
regression model and shown to have very good accuracy.
An erratum to this article can be found at 相似文献
2.
A one-term Edgeworth expansion for U-statistics with kernel h(x, y) was derived by Jing and Wang [3] under optimal moment conditions. In this note, we show that one of the optimal moment conditions
E| h(X
1, X
2|5/3 < ∞ can be weakened to lim
t→∞
t
5/3
P(|h(X
1, X
2)| > t) → 0.
Printed in Lietuvos Matematikos Rinkinys, Vol. 45, No. 3, pp. 453–440, July–September, 2005. 相似文献
3.
In this paper, we propose approximations to compute the steady-state performance measures of the M/GI/N+GI queue receiving Poisson arrivals with N identical servers, and general service and abandonment-time distributions. The approximations are based on scaling a single
server M/GI/1+GI queue. For problems involving deterministic and exponential abandon times distributions, we suggest a practical way to compute
the waiting time distributions and their moments using the Laplace transform of the workload density function. Our first contribution
is numerically computing the workload density function in the M/GI/1+GI queue when the abandon times follow general distributions different from the deterministic and exponential distributions.
Then we compute the waiting time distributions and their moments. Next, we scale-up the M/GI/1+GI queue giving rise to our approximations to capture the behavior of the multi-server system. We conduct extensive numerical
experiments to test the speed and performance of the approximations, which prove the accuracy of their predictions.
相似文献
4.
G. Falin 《Queueing Systems》2008,58(1):65-76
We consider the M/M/∞ queueing system with arrival and service rate depending on the state of an auxiliary semi-Markov process (which can be
viewed as an external environment) and find the mean number of customers in the system in steady state. In a particular case
when the external environment can be only in two states we find the distribution of the number of customers in the system.
相似文献
5.
We investigate GI
X
/M(n)//N systems with stochastic customer acceptance policy, function of the customer batch size and the number of customers in the
system at its arrival. We address the time-dependent and long-run analysis of the number of customers in the system at prearrivals
and postarrivals of batches and seen by customers at their arrival to the system, as well as customer blocking probabilities.
These results are then used to derive the continuous-time long-run distribution of the number of customers in the system.
Our analysis combines Markov chain embedding with uniformization and uses stochastic ordering as a way to bound the errors
of the computed performance measures.
相似文献
6.
G. I. Falin 《Queueing Systems》2008,58(3):155-160
Sherman and Kharoufeh (Oper. Res. Lett. 34:697–705, [2006]) considered an M/M/1 type queueing system with unreliable server and retrials. In this model it is assumed that if the server fails during service
of a customer, the customer leaves the server, joins a retrial group and in random intervals repeats attempts to get service.
We suggest an alternative method for analysis of the Markov process, which describes the functioning of the system, and find
the joint distribution of the server state, the number of customers in the queue and the number of customers in the retrial
group in steady state.
相似文献
7.
We derive fast recursions to compute the probability that k or more consecutive customer losses take place during a busy period of a queue, the so called k-CCL probability, for regular and oscillating M
X
/G/1/n systems. 相似文献
8.
A. M. Bratiichuk 《Ukrainian Mathematical Journal》2007,59(9):1300-1312
For finite-capacity queuing systems of the type M
θ/G/1, convenient formulas for the ergodic distribution of the queue length are found, an estimate for the rate of convergence
of the distribution of the queue length in the transient mode to the ergodic distribution is obtained, and computational algorithms
for finding the rate of convergence are presented.
__________
Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 59, No. 9, pp. 1169–1178, September, 2007. 相似文献
9.
William D. BANKS Florian LUCA 《数学学报(英文版)》2007,23(10):1915-1918
In this note, we show that the number of composite integers n ≤ x such that φ(n)|n - 1 is at most O(x^1/2(loglog x)^1/2), thus improving earlier results by Pomerance and by Shan. 相似文献
10.
The purpose of the “bootstrap program” for integrable quantum field theories in 1+1 dimensions is to construct a model explicitly
in terms of its Wightman functions. We illustrate this program here mainly in terms of the SU(N) Gross-Neveu model. We construct
the nested off-shell Bethe ansatz for an SU(N) factoring S-matrix and consider the problem of how to sum over intermediate
states in the short-distance limit of the two-point Wightman function for the sinh-Gordon model.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 155, No. 1, pp. 13–24, April, 2008. 相似文献
11.
We consider the M/M/1 queue with processor sharing. We study the conditional sojourn time distribution, conditioned on the customer’s service
requirement, in various asymptotic limits. These include large time and/or large service request, and heavy traffic, where
the arrival rate is only slightly less than the service rate. The asymptotic formulas relate to, and extend, some results
of Morrison (SIAM J. Appl. Math. 45:152–167, [1985]) and Flatto (Ann. Appl. Probab. 7:382–409, [1997]).
This work was partly supported by NSF grant DMS 05-03745. 相似文献
12.
Let ƒ be a transcendental meromorphic function, a a nonzero finite complex number, and n ⩾ 2 a positive integer. Then ƒ + a(ƒ′)
n
assumes every complex value infinitely often. This answers a question of Ye for n = 2. A related normality criterion is also given.
This work was supported by the National Natural Science Foundation of China (Grant No. 10771076), the Natural Science Foundation
of Guangdong Province, China (Grant No. 07006700) and by the German-Israeli Foundation for Scientific Research and Development
(Grant No. G-809-234.6/2003) 相似文献
13.
We describe four different types of N=(4, 4) twisted supermultiplets in the two-dimensional N=(2, 2) superspace ℝ(1,1|2,2). All these multiplets are represented by a pair of chiral and twisted chiral superfields and differ in the transformation
properties under an extra hidden N=(2, 2) supersymmetry. The sigma-model N=(2, 2) superfield Lagrangians for each type of
the N=(4, 4) twisted supermultiplet are real functions subjected to some differential constraints implied by the hidden supersymmetry.
We prove that the general sigma-model action including all types of N=(4, 4) twisted multiplets and invariant under the N=(4,
4) supersymmetry reduces to a sum of sigma-model actions for separate types. An interaction between the multiplets of different
sorts is possible only through the appropriate mass terms and only for those multiplets that belong to the same “self-dual”
pair.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 145, No. 1, pp. 66–86, October, 2005. 相似文献
14.
Jinjin Li 《Czechoslovak Mathematical Journal》2005,55(4):941-945
In this note we study the relation between k
R
-spaces and k-spaces and prove that a k
R
-space with a σ-hereditarily closure-preserving k-network consisting of compact subsets is a k-space, and that a k
R
-space with a point-countable k-network consisting of compact subsets need not be a k-space.
This work was supported by the NSF of China (10271056). 相似文献
15.
16.
P. Oswald 《Journal of Mathematical Sciences》2008,155(1):109-128
In [9], we proved numerically that spaces generated by linear combinations of some two-dimensional Haar functions exhibit
unexpectedly nice orders of approximation for solutions of the single-layer potential equation in a rectangle. This phenomenon
is closely related, on the one hand, to the properties of the approximation method of hyperbolic crosses and on the other
to the existence of a strong singularity for solutions of such boundary integral equations. In the present paper, we establish
several results on the approximation for the hyperbolic crosses and on the best N-term approximations by linear combinations of Haar functions in the H
s
-norms, −1 < s < 1/2; this provides a theoretical base for our numerical research. To the author's best knowledge, the negative smoothness
case s < 0 was not studied earlier.
__________
Translated from Sovremennaya Matematika. Fundamental'nye Napravleniya (Contemporary Mathematics. Fundamental Directions),
Vol. 25, Theory of Functions, 2007. 相似文献
17.
18.
A. V. Smirnov 《Theoretical and Mathematical Physics》2009,158(3):300-312
We show a relation between systems of integrable tops on the algebras sl(N, ℂ) and Calogero-Moser systems of N particles. We construct classical Lax operators corresponding to these systems. We show
that these operators are related to certain new trigonometric and rational solutions of the Yang-Baxter equations for the
algebras sl(N, ℂ) and give explicit formulas for N = 2, 3.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 158, No. 3, pp. 355–369, March, 2009. 相似文献
19.
Goran Muić 《Israel Journal of Mathematics》2008,164(1):87-124
The purpose of this paper is to prove some fundamental results on the structure of theta lifts of discrete series. 相似文献
20.
We consider an M
[X]/G/1 retrial queue subject to breakdowns where the retrial time is exponential and independent of the number of customers applying
for service. If a coming batch of customers finds the server idle, one of the arriving customers begins his service immediately
and the rest joins a retrial group (called orbit) to repeat his request later; otherwise, if the server is busy or down, all
customers of the coming batch enter the orbit. It is assumed that the server has a constant failure rate and arbitrary repair
time distribution. We study the ergodicity of the embedded Markov chain, its stationary distribution and the joint distribution
of the server state and the orbit size in steady-state. The orbit and system size distributions are obtained as well as some
performance measures of the system. The stochastic decomposition property and the asymptotic behavior under high rate of retrials
are discussed. We also analyse some reliability problems, the k-busy period and the ordinary busy period of our retrial queue. Besides, we give a recursive scheme to compute the distribution
of the number of served customers during the k-busy period and the ordinary busy period. The effects of several parameters on the system are analysed numerically.
I. Atencia’s and Moreno’s research is supported by the MEC through the project MTM2005-01248. 相似文献