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Published on: July 3, 2020
Signed log-likelihood ratio test for the scale parameter of Poisson Inverse Weibull distribution with the development
Sukanya Yodnual1, Jularat Chumnaul1
1Division of Computational Science, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla, Thailand.
The signed log-likelihood ratio test (SLRT) offers a robust method for analyzing system failure times using the Poisson Inverse Weibull (PIW) distribution. It outperforms asymptotic normality of maximum likelihood estimators (ANMLE), especially in small samples, ensuring reliable statistical inference.
Area of Science:
- Statistics
- Reliability Engineering
- Survival Analysis
Background:
- The Poisson Inverse Weibull (PIW) distribution provides a flexible model for system failure times.
- Hypothesis testing for parameters in complex distributions is crucial for accurate reliability analysis.
Purpose of the Study:
- Introduce and evaluate the signed log-likelihood ratio test (SLRT) for the scale parameter of the PIW distribution.
- Compare the performance of SLRT against the asymptotic normality of maximum likelihood estimators (ANMLE) test.
Main Methods:
- Simulation studies were conducted to assess Type I error rates and empirical power.
- The SLRT's performance was evaluated across various sample sizes and parameter configurations.
- A web application, PIW4LIFETIME, was developed for practical implementation.
Main Results:
- SLRT consistently maintained Type I error rates within the acceptable range (0.04-0.06) at a 0.05 significance level.
- SLRT demonstrated superior empirical power compared to ANMLE, particularly in small samples (n=10, 15).
- ANMLE was often conservative and showed lower power in small samples, though its power approached SLRT's with larger sample sizes.
Conclusions:
- The SLRT is a robust and reliable method for hypothesis testing in the PIW distribution, outperforming ANMLE, especially with limited data.
- The developed PIW4LIFETIME web application facilitates practical application of the SLRT for analyzing system failure data.
- The study highlights the SLRT's effectiveness and the utility of the PIW distribution in reliability engineering.
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