在這篇文章中，我們討論在刪減區間資料下有關韋伯分佈參數的推論，並提出兩個檢定統計量用來比較兩個韋伯分佈。然而，這兩個檢定統計量的分佈是未知的而且不容易求得，因此一個有關模擬的研究是必須的。在刪減區間資料的模擬中，一個甕模型被黎進三教授在1999年提出，可用來選取隨機區間。則我們利用甕模型而提出一個模擬的步驟去得到兩個統計量的分位數的近似值。我們舉一個在AIDS研究中的例子，說明我們所提出的檢定量如何應用在AIDS感染時間的分佈上。

In this article, we make inferences for the Weibull parameters and propose two test statistics for the comparison of two Weibull
distributions based on interval-censored data. However, the distributions of the two statistics are unknown and not easy to obtain, therefore a simulation study is necessary. An urn model
in the simulation of interval-censored data was proposed by Lee (1999) to select random intervals. Then we propose a simulation
procedure with urn model to obtain approximately the quantiles of the two statistics. We demonstrate an example in AIDS study to
illustrate how the tests can be applied to the infection time distributions of AIDS.

1 Introduction

2 Comparison of two Weibull distribution based
on interval-censored data

2.1 Equivariant estimators and pivotal
quantities for a location-scale parameter
distribution based on interval-censored
data

2.2 Confidence interval construction and the
comparison of parameters

3 A method of simulation

3.1 Turnbull's iterative algorithm

3.2 An urn model

3.3 Maximum likelihood estimates based on an
interval-censored sample

3.4 Simulation procedures

4 Application

4.1 Estimate p with Turnbull's iterative
algorithm
4.2 Graphics method for Weibull or extreme
value model
4.3 Simulation and results

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