研究方向

考慮K個韋伯母體π_i，i=1,……,k。設我們有興趣的參數為其某一固定時間的可靠度，本人在Leu(2001)已研究出如何選取最佳母體的方法。若我們希望選取的集合包含較好的母體，對於指數母體，本人在Leu(2000)亦討論過。我們對韋伯母體的處理方式，可以考慮作對數轉換，將此問題化成極值分配問題。

對此問題的數值解，除了理論上的探討外，我們亦可以利用模擬方法加以解決。重抽樣方法也是一個可考慮的方向。

預燒是為了減少產品早衰的生產過程必要的手段。Jensen 及 Peterson(1982)，Bergman(1985)，Clarotti 及 Spizzichino(1990) 提出一簡單的方法來決定終止試驗的時間。Spizzichino(1991) 提出同時預燒的問題。Runggaldier(1993) 利用隨機控制的方法來處理最佳停止問題。若我們假設產品為韋伯分配，我們提出一最適方法，利用一簡單的例子說明我們方法的優點。

Research Interest

Consider K Weibull populations π_i, i=1,……,k.Suppose that the parameters of interest are reliability of a given fixed time.We have discussed the selection program in Leu(2001).If we hope the selected subset contains only good populations,we dealed this problem for exponential populations in Leu(2000).For the Weibull population problem,we make a log transformation and deal the Extreme Value problems.

For the numerical solutions,we have some theoretical results,we can also solve it by simulation.Further,resampling method is also a possible selection.

Burn-in is a manufacturing operation that is intended to eliminate early failure.Jensen and Peterson(1982),Bergman(1985),and Clarotti and Spizzichino(1990) provided a simple method to judge if the procedure should terminate.Spizzichino(1991) consider the case that there are n components have been burned-in simultaneously.Runggaldier(1993) use the approaches of stochastic control to deal with the optimal stopping problem.Under the assumption of Weibull distributions,we propose an optimal strategy.We will show the benift of our procedure by a simple example.

Selected Recent Publications:

1. Y. C. Chang and L. Y. Leu, 1998, A State Space Model for Software Reliability Ann. Inst. Statist. Math., Vol. 50, No. 4, 789-799.

2. L. Y. Leu and J. C. Wu, 1999, A Dynamic Bayesian Approach to Inference from Accelerated Life Tests, Commun. Statist,. Simul, and Comput., Vol. 28, 37-49.

3. J.C.Wu and L.Y.Leu,2000, A Two-Stage Procedure with Accelerated Test for Selecting the Best Exponential

Population , Commun,Staist,Theory Math.,Vol29(2),369-380.

4.L.Y.Leu,2000,On Restricted Subset Selection Rules For Selecting the Best Exponential Population.Research Report.

5.L.Y.Leu,2001,Selection Problems on Weibull Distributions.Research Report.

6.Y.C.Chang and L.Y.Leu,2001,An Optimal Sequetial Burn-in Procedure.Research Report.