Residual Control Charts for Improving Changeover Productivity

Abstract

Although statistical control charts have been popularly used in monitoring process quality, the concepts of statistical control are essentially suited to the improvement of productivity in virtually any area of business. This article presents a new statistical control chart, the residual control chart, which was employed to improve machine changeover productivity in a textile manufacturing company. To control productivity of various manned operations, the authors identified variation due to the performance of technicians while controlling for the effect of other factors. Instead of making numerous charts for individual categories, the proposed control chart reduces the number of charts, while still blocking out the effect of extraneous factors. The residual chart may be used to help managers balance workloads, plan training programs, and/or assist in conducting performance appraisals.