Résumé:
This memory focuses on Step-Stress Partially Accelerated Life Tests (SS-PALT) applied
to products with a two-parameter bathtub-shaped lifetime distribution, specifically
the Chen distribution. The objective is to estimate the distribution parameters and
acceleration factor using maximum likelihood estimation (MLE) based on progressive
Type-II censoring. The thesis also provides the asymptotic variance and covariance
matrix of the estimators. To establish confidence intervals (CIs) for the parameters,
two approaches are employed: the normal approximation to the asymptotic distribution
of the MLEs and the bootstrap method. The estimators are numerically obtained
using the Mathematica Package through an iterative procedure. To demonstrate the
proposed estimation method, a numerical example is presented. Furthermore, a realworld
example is provided to illustrate the suggested approach.
Keywords: Chen distribution; Step-stress partially accelerated life tests; Progressive Type-II censoring; Maximum likelihood estimation; Asymptotic confidence intervals
