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Published on: October 23, 2020
Parametric inference on partially accelerated life testing for the inverted Kumaraswamy distribution based on Type-II
Manal M Yousef1, Rehab Alsultan2, Said G Nassr3,4
1Department of Mathematics, Faculty of Science, New Valley University, El-Khargah 72511, Egypt.
This study estimates parameters for products under step stress accelerated life testing using Type-II progressively censored data. It applies maximum likelihood and Bayesian methods for reliable reliability estimation.
Area of Science:
- Reliability Engineering
- Statistical Inference
- Accelerated Life Testing
Background:
- Estimating product lifetime under stress is crucial for reliability.
- Traditional life testing can be time-consuming and expensive.
- Accelerated life testing (ALT) methods reduce testing time by applying higher stress levels.
Purpose of the Study:
- To develop estimation methods for step-stress partially accelerated life tests (SS-PALT) with Type-II progressively censored data.
- To model product lifetimes using the two-parameter inverted Kumaraswamy distribution.
- To compare the performance of Maximum Likelihood Estimation (MLE) and Bayesian estimation techniques.
Main Methods:
- Utilizing Type-II progressive censoring for efficient data collection.
- Calculating numerical Maximum Likelihood Estimates (MLEs) for unknown parameters.
- Constructing asymptotic interval estimates based on MLE properties.
- Applying Bayesian inference with symmetric and asymmetric loss functions.
- Employing Lindley's approximation and Markov Chain Monte Carlo (MCMC) for Bayes estimates.
- Calculating Highest Posterior Density (HPD) credible intervals.
Main Results:
- Numerical MLEs were computed for model parameters.
- Asymptotic confidence intervals were derived.
- Bayesian estimates were obtained using Lindley's approximation and MCMC.
- HPD credible intervals provided uncertainty quantification for parameters.
- The study demonstrated practical application through a real-world example.
Conclusions:
- Both MLE and Bayesian methods provide viable approaches for parameter estimation in SS-PALT.
- The inverted Kumaraswamy distribution is suitable for modeling lifetimes under these conditions.
- Progressive censoring enhances the efficiency of life testing experiments.
- The proposed methods offer robust tools for reliability assessment in engineering applications.
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