An Integrated Approach for Designing a Sampling Plan and Fixing Specifications

In 1986 Taguchi presented the quadratic function for describing the loss of quality due to deviation from the production value. The objective then is to improve quality by minimizing the quadratic loss function which reflects the loss of both, the producer and the consumer. Subsequently, Kapur et al. (Wang, Economic design of specifications based on Taguchi's concept of quality loss function.: 23-36, 1987, Quality Engineering 1:63-77, 1988, Cho, Quality Engineering 6: 401-417, 1994) addressed the problem of deriving a loss function to be applied for determining the design of specification limits. This article further explores the problem of determining an integrated design of a Type I continuous sampling plan (CSP-1) and the specification limits. By modifying Kapur and Wang's (Economic design of specifications based on Taguchi's concept of quality loss function.: 23-36, 1987) model, we not only obtain economic specification limits, but also obtaib an optimal CSP-1 plan for inspection.