ASQ RRD series webinar: How to Graph, Analyze, and Compare Sets of Repair Data
Presenter: Dr. Wayne B. Nelson
Thursday, February 13, 2025 12:00 PM – 1:00 PM
(UTC-04:00) Eastern Time (US & Canada)
https://asq.webex.com/weblink/register/r376b7d4ec0dc388988abf96d0af86142
Abstract:
Many products accumulate repeated repairs and repair costs over time. Analysis of such recurrence data requires special statistical models and methods not covered in basic reliability books.
This webinar presents a general simple and informative model and plot for analyzing data on numbers or costs of repeated repairs of a sample of units.
The plot provides:
1. An estimate of the average number or cost of repairs per unit during warranty or design life.
2. The behavior of the population repair rate – does it increase or decrease with population age? This information is used to make decisions on product burn-in, overhaul, preventive replacement, and retirement.
3. Predictions of the future number or cost of repairs for a unit or the population. This is used to predict warranty costs and the demand for replacement parts.
4. A comparison of data sets from different populations. This is used to decide which designs, materials, treatments, environments, etc., produce lower repair rates.
5. Unsought useful information. The plots and analyses are illustrated with data on car transmission repairs, bladder tumor recurrences, childbirths to statisticians, amazon.com sales, and other applications. Computer programs
that calculate and make the plots and comparisons with confidence limits are surveyed.