Censoring Methodologies and Censored Data Analysis with Applications in the Engineering and Environmental Sciences

删失发生在有关观测的信息缺失或仅部分可用时。有各种类型的审查，其中一些被纳入研究设计，其中一些自然发生，一个没有控制。删失数据出现在各个领域，从制药行业的临床试验到工程科学中的生命测试，再到环境科学中的森林火灾蔓延建模。因此，至关重要的是要有必要的工具来分析这些数据，并作出有用的推论。寿命试验是可靠性分析中的一种有效方法，工程师在试验中对部件进行寿命试验，并试图对部件的寿命分布作出有用的推断。在这些测试中，通常采用某种类型的审查来节省时间和金钱等资源。一种特殊类型的审查是渐进审查，这是本研究计划的重点。在逐步删失实验中，根据预先指定的方案，在整个寿命测试中随机移除存活单元。 这种类型的删失可以是寿命试验设计的一部分，并且比传统类型的删失更通用，因此特别有用。 在这个问题上，我介绍了有限的渐进删失计划，以及调查一步计划，这是特殊的计划，需要幸存的单位被随机删除在一个故障时间。尽管这两种审查具有限制性，但从实际角度来看，这些计划具有特别的好处。庞巴迪公司等公司的研究部门，在组件的可靠性至关重要且需要审查的情况下，将能够从这项工作中受益。

Censoring occurs when information about observations is either missing or only partially available. There are various types of censoring, some of which are incorporated into the design of a study, some of which occur naturally and one has no control over. Censored data arise in various fields, ranging from clinical trials in the pharmaceutical industry, to life-tests in the engineering sciences, to the modelling of the spread of a forest fire in the environmental sciences. It is therefore crucial to have the necessary tools to analyze such data and make useful inferences. A life-test, wherein an engineer puts units on test and attempts to make useful inferences about the units' lifetime distribution, is an effective technique employed in reliability analysis. In these tests, some type of censoring is often employed to save resources like time and money. One particular type of censoring is progressive censoring, which is a focus of this research program. In a progressive censoring experiment, surviving units are randomly removed throughout the life-test according to a prespecified scheme.  This type of censoring can be part of the design of a life-test and is more versatile than the traditional types of censoring, and hence is particularly useful.  On this topic, I introduce restricted progressive censoring schemes as well as investigate one-step plans, which are special plans entailing surviving units being randomly removed at one failure time. Despite the restrictive nature of these two types of censoring, these plans have particular benefits from practical points of view. Research departments in companies like Bombardier Inc., where reliability of components is critical and censoring is needed, will be able to benefit from this work.