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<p>Dear all, </p>
<p>On Thursday (12 December) at 2pm in <span class="event-where">54 / 10037 (10B), we have an S3RI seminar from Maria Kateri (RWTH Aachen University) on
</span><span class="event-where"><span class="event-description">"</span></span><span class="event-where"><span class="event-description"><span class="event-description"><span class="event-description">Step-Stress Accelerated Life Testing Models: Statistical
Inference and Optimal Design of Experiments</span></span>". Details are given below.<br>
</span></span></p>
<p><span class="event-where"><span class="event-description"><span><span class="event-description">The talk will be followed by tea and cake in the staff reading room on level 4 of building 54. </span></span></span></span></p>
<p><span class="event-where"><span class="event-description"><span><span class="event-description">All are welcome!</span></span></span></span></p>
<p><span class="event-where"><span class="event-description"><span>Best wishes,</span></span></span></p>
<p><span class="event-where"><span class="event-description"><span>Helen</span></span></span></p>
<p><span class="event-description">Step-Stress Accelerated Life Testing Models: Statistical Inference and Optimal Design of Experiments</span></p>
<p><span class="event-description">Maria Kateri, Institute of Statistics, RWTH Aachen University
<br>
</span></p>
<p><span class="event-description">Life testing is a major issue in reliability analysis with applications in diverse fields, ranging from material sciences and quality control to biomedical sciences and ecology statistics. In all these fields acceleration
of life testing procedures is important. Step-stress models form an essential part of accelerated life testing (ALT). Under a step-stress ALT (SSALT) model, the test units are exposed to stress levels that increase at intermediate time points of the experiment.
Statistical inference is then developed for, e.g., the mean lifetime under each stress level, targeting to the extrapolation under normal operating conditions. This is achieved through an appropriate link function that connects the stress level to the associated
mean lifetime. The assumptions made about the time points of stress level change, the termination point of the experiment, the underlying lifetime distributions, the type of censoring, if present, and the way of monitoring, lead to respective models.
<br>
</span></p>
<p><span class="event-description">Αn SSALT model is introduced that considers a general scale family of distributions, which allows for flexible modeling. It is based on a failure rate approach and leads to explicit expressions for the maximum likelihood estimators
of the scale parameters of the underlying lifetime distributions out of this family. The approach is presented for Type-I censored experiments under interval monitoring of the tested items. The points of stress-level change are simultaneously inspection points
as well, while there is the option of assigning additional inspection points in between the stress-level change points. Statistical inference, frequentist and Bayes, as well as the issue of optimal designing an SSALT experiment are discussed.</span></p>
<br>
<span class="event-where"><span class="event-description"><span><span class="event-description"><span><span class="event-description"></span><span class="event-description"><span class="event-description">For the current schedule of S3RI seminars, see
<a class="moz-txt-link-freetext" href="https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Ftinyurl.com%2Fs3riseminar&data=01%7C01%7C%7Cc05734b9ff1c43657fde08d77d420eb0%7C4a5378f929f44d3ebe89669d03ada9d8%7C0&sdata=zJ3YqM7EM8iojd1G%2BMsUemDJ0oelueYzrOzY7viJH5c%3D&reserved=0" originalsrc="https://tinyurl.com/s3riseminar" shash="Rj/gTH3Eu3QH6Fauqjmqoj0TCcVIbVSAUte/oeZhLw4nUVVJp/gbNO7ow8Ixyi5IPmWWqDJqrzn0kT3RpaGj3kgdTbSJmjLQJtJ7Em8p1SA32s9uevbgqn6g6mSOpzDsEp7dtJ3oc/CBelYtbjXNPn26lkN6dAO1uVueyhrsT/8=">
https://tinyurl.com/s3riseminar</a> </span></span></span></span></span></span></span>
<p><span class="event-where"><span class="event-description"><span><span class="event-description"></span></span></span></span></p>
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