Related Experiment Video
Updated: Jun 30, 2026

10:00
Measurement of Lifespan in Drosophila melanogaster
Published on: January 7, 2013
Acceptance sampling based on truncated life tests in the Birnbaum Saunders model
Ayman Baklizi1, Abed El Qader El Masri
1Department of Statistics, Yarmouk University, Irbid, Jordan. baklizi@hotmail.com
Summary
This study introduces acceptance sampling plans for products with lifetimes following the Birnbaum-Saunders distribution, using truncated life tests. It determines the minimum sample size needed to achieve a target average life, ensuring quality control with defined risks.
Area of Science:
- Reliability Engineering
- Statistical Quality Control
- Probability Distributions
Background:
- Acceptance sampling plans are crucial for quality control in manufacturing.
- Traditional methods often assume complete life testing, which can be time-consuming and costly.
- The Birnbaum-Saunders distribution is suitable for modeling fatigue and failure times.
Purpose of the Study:
- To develop and present acceptance sampling plans based on truncated life tests.
- To determine the minimum sample size required for a specified average product life.
- To evaluate the operating characteristic values and producer's risk associated with these plans.
Main Methods:
- Utilizing the Birnbaum-Saunders distribution to model unit lifetimes.
- Implementing a truncated life testing procedure.
- Calculating minimum sample sizes and operating characteristic curves.
- Presenting producer's risk associated with the developed plans.
Main Results:
- The study provides a method for determining minimum sample sizes for acceptance sampling under truncated tests.
- Operating characteristic values and producer's risk are quantified for the proposed plans.
- An illustrative example demonstrates the practical application of the developed methodology.
Conclusions:
- The developed acceptance sampling plans offer an efficient approach for quality control when life testing is truncated.
- The methodology allows for the determination of adequate sample sizes to meet desired reliability standards.
- These plans are valuable for industries seeking to optimize testing procedures while managing risks.
Related Concept Videos
Introduction To Survival Analysis
Survival analysis is a statistical method used to study time-to-event data, where the "event" might represent outcomes like death, disease relapse, system failure, or recovery. A unique feature of survival data is censoring, which occurs when the event of interest has not been observed for some individuals during the study period. This requires specialized techniques to handle incomplete data effectively.
The primary goal of survival analysis is to estimate survival time—the time until a...
The primary goal of survival analysis is to estimate survival time—the time until a...
Life Tables
A life table is a statistical tool that summarizes the mortality and survival patterns of a population, providing detailed insights into the likelihood of survival or death across different age intervals within a cohort. By organizing data on survival probabilities and mortality rates, life tables offer a clear snapshot of population dynamics over time. They are extensively used in demography, public health, actuarial science, and ecology to analyze life expectancy, design health interventions,...
Actuarial Approach
The actuarial approach, a statistical method originally developed for life insurance risk assessment, is widely used to calculate survival rates in clinical and population studies. This method accounts for participants lost to follow-up or those who die from causes unrelated to the study, ensuring a more accurate representation of survival probabilities.
Consider the example of a high-risk surgical procedure with significant early-stage mortality. A two-year clinical study is conducted,...
Consider the example of a high-risk surgical procedure with significant early-stage mortality. A two-year clinical study is conducted,...
Kaplan-Meier Approach
The Kaplan-Meier estimator is a non-parametric method used to estimate the survival function from time-to-event data. In medical research, it is frequently employed to measure the proportion of patients surviving for a certain period after treatment. This estimator is fundamental in analyzing time-to-event data, making it indispensable in clinical trials, epidemiological studies, and reliability engineering. By estimating survival probabilities, researchers can evaluate treatment effectiveness,...
Assumptions of Survival Analysis
Survival models analyze the time until one or more events occur, such as death in biological organisms or failure in mechanical systems. These models are widely used across fields like medicine, biology, engineering, and public health to study time-to-event phenomena. To ensure accurate results, survival analysis relies on key assumptions and careful study design.
Truncation in Survival Analysis
Truncation in survival analysis refers to the exclusion of individuals or events from the dataset based on specific criteria related to the time of the event. This exclusion can happen in two primary forms: left truncation and right truncation.
Left truncation occurs when individuals who experienced the event of interest before a certain time are not included in the study. This is often due to a "delayed entry" into the study where only those who survive until a certain entry point are observed.
Left truncation occurs when individuals who experienced the event of interest before a certain time are not included in the study. This is often due to a "delayed entry" into the study where only those who survive until a certain entry point are observed.

