Car Crash

A student crashes a car through the main entrance of Brock University and ransacks the office of the University President. The Buick La Sabre is driven through the glass doors of the Schmon Tower in the early morning, just as staff are beginning to report for work. The occupant of the vehicle proceeds to the tower's thirteenth floor, where he overturns furniture in the President's offices and breaks windows. University officials find him sitting in the President's chair, claiming he is God or Jesus.

Optimal and Robust Designs of Step-stress Accelerated Life Testing Experiments for Proportional Hazards Models

Accelerated life testing (ALT) is widely used to obtain reliability information about a product within a limited time frame. The Cox s proportional hazards (PH) model is often utilized for reliability prediction. My master thesis research focuses on designing accelerated life testing experiments for reliability estimation. We consider multiple step-stress ALT plans with censoring. The optimal stress levels and times of changing the stress levels are investigated. We discuss the optimal designs under three optimality criteria. They are D-, A- and Q-optimal designs. We note that the classical designs are optimal only if the model assumed is correct. Due to the nature of prediction made from ALT experimental data, attained under the stress levels higher than the normal condition, extrapolation is encountered. In such case, the assumed model cannot be tested. Therefore, for possible imprecision in the assumed PH model, the method of construction for robust designs is also explored.