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41.
In precedence tests, the test powers are given by the probabilities P(Y(i) > X(j)) for some i and j, where X(j) and Y(i) are the order statistics of two independent random samples. Such probabilities can also arise in reliability theory. In this paper, we investigate the properties of these probabilities and their applications.  相似文献   
42.
This paper looks at the optimization of a production line similar to a just-in-time ( JIT) production flow line. It discusses the planning process, the types of products that can be ff e ectively processed on a JIT line, and the presently available procedures that should be followed when trying to optimize the production line. The article discusses the shortcomings of these techniques, then, based on research investigations, proceeds to recommend a process that will help assure optimization of a JIT process.  相似文献   
43.
Hader and Park (1978) introduced second order slope rotatability in axial directions. Park (1987) introduced second order slope rotatabilty over all directions. It is shown that these designs have the additional properly that the sum of the variances of estimates of slopes in all directions at any point is a function of the distance of the point from the design origin.  相似文献   
44.
In this paper we present analogues of Balakrishnan's (1989) relations that relate the triple and quadruple moments of order statistics from independent and nonidentically distributed (I.NI.D.) random variables from a symmetric distribution to those of the folded distribution. We then apply these results, along with the corresponding recurrence relations for the exponential distribution derived recently by Childs (2003), to study the robustness of the Winsorized variance.  相似文献   
45.
This paper investigates, by means of Monte Carlo simulation, the effects of different choices of order for autoregressive approximation on the fully efficient parameter estimates for autoregressive moving average models. Four order selection criteria, AIC, BIC, HQ and PKK, were compared and different model structures with varying sample sizes were used to contrast the performance of the criteria. Some asymptotic results which provide a useful guide for assessing the performance of these criteria are presented. The results of this comparison show that there are marked differences in the accuracy implied using these alternative criteria in small sample situations and that it is preferable to apply BIC criterion, which leads to greater precision of Gaussian likelihood estimates, in such cases. Implications of the findings of this study for the estimation of time series models are highlighted.  相似文献   
46.
The main focus of studies on ethnic Chinese in Southeast Asia is generally their business acumen or the extent to which they are assimilated into their respective country of residence. This paper concentrates on a rather different aspect among this ethnic group, namely the influence of Islam amongst the Chinese, especially in Indonesia and Malaysia. This is a topic on which very little research has been done, especially in terms of identity and ethnicity together with processes of integration and assimilation—in relation to both other ethnic Chinese and the local communities in which they are socially imbedded. Because of the deficiency of empirical data, it is imperative that we understand the historical processes that lead up to the present marginalised position of this group of Chinese. As a consequence, the present paper employs a historical approach towards the study of the Chinese Muslims in their respective local communities.  相似文献   
47.
学习英文在语法、词汇两方面存在着中英、英英差别。“通过比较、找出差别、加深理解”的学习方法在培养学生的阅读、写作、翻译以及综合运用能力方面起着重要作用。比较研究法作为一种学习和思维方法,不仅适用于高校外语教学,有利于提高学生解决问题的能力,同时在第二外语习得以及跨文化交流中也同样具有重要意义。  相似文献   
48.
Let X be a discrete random variable the set of possible values (finite or infinite) of which can be arranged as an increasing sequence of real numbers a1<a2<a3<…. In particular, ai could be equal to i for all i. Let X1nX2n≦?≦Xnn denote the order statistics in a random sample of size n drawn from the distribution of X, where n is a fixed integer ≧2. Then, we show that for some arbitrary fixed k(2≦kn), independence of the event {Xkn=X1n} and X1n is equivalent to X being either degenerate or geometric. We also show that the montonicity in i of P{Xkn = X1n | X1n = ai} is equivalent to X having the IFR (DFR) property. Let ai = i and G(i) = P(X≧i), i = 1, 2, …. We prove that the independence of {X2n ? X1nB} and X1n for all i is equivalent to X being geometric, where B = {m} (B = {m,m+1,…}), provided G(i) = qi?1, 1≦im+2 (1≦im+1), where 0<q<1.  相似文献   
49.
This article proposes estimating the mean of positively skewed distributions by a one-sided trimmed mean estimator, called the upper-mean, and uses it to assess soil contact exposures at sites with toxic contamination. An optimal upper-mean is found by maximising the probability of the estimator falling in a target range. Monte Carlo studies are conducted for several positively skewed distributions and for a distribution obtained from real data. The simulation results show that the upper-mean is a better estimator than the upper 95% confidence limit estimator currently used, because it is more probable that the estimator is covered by the target range.  相似文献   
50.
本文讨论了一阶非线性滞后型微分方程组■,(1)所有解振荡的充分条件,发展了文[1]的方法,并推广强化了文[1]的有关结论。  相似文献   
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