This document presents a study on developing mathematical expressions to calculate quality costs (QC) in a production-supply line. It discusses:
1. Classifying QC using the PAF (Prevention, Appraisal, Failure) model and developing expressions to estimate QC factors like number of right/faulty products.
2. Collecting data on QC from the supply line over two time periods - an initial "quality immaturity" period and a subsequent "quality maturity" period.
3. Analyzing the data to show it follows two different behavior patterns over time - the initial data follows Juran's quality cost model while the later data follows a continuous improvement model, indicating increasing quality maturity.