Deterioration: a statistical quality control analysis
by
Gauri Shankar
S.O.S. in Statistics, Pandit R.S. University, Raipur, M.P. India

The structural basis of deterioration demonstrated with control line emphasises the need and importance of a scientific approach of judgement to achieve ultimate control over a (non-necessarily) physical system/process. Evaluation of corrective action models through two statistical measures of deterioration, namely, vertical and horizontal, reveals that a system can be controlled by taking appropriate correctives only at the early stage of vertical measure, contrary to a la mode at horizontal measure. A sequence of vertical-horizontal-vertical measure formed due to a shift of control-line towards out-of-control region makes the statistical basis of deterioration.

Date received: November 14, 2000