Choosing a lower specification limit for an exponential process with ‘the larger the better’ tolerance: a simple, exact solution

Chen (1999) proposed an economic design, using Taguchiʹs quality loss function, for choosing a producerʹs lower specification limit eta for a product with a quality characteristic that has an exponential distribution with mean &thetas; and ʹthe larger the betterʹ tolerance. Chen (1999) developed an approximate solution that is applicable when 0.5 r m/&thetas; r 0.7 and that requires numerical minimization. We derive a simple, exact solution that is applicable for all values of m/&thetas; and does not require numerical minimization.