AMS 109

The use of statistical techniques such as control charts to analyze a process or its output so as to take appropriate actions to achieve and maintain a state of statistical control and to improve the process capability.

• statistical study

• quality control

• statistical process control

• process engineering

The condition describing a process from which the effect of all special causes of variation have been eliminated and only that due to common causes remain.

• consistent

• statistical control

• stable

• process control

Qualitative data that can be categorized for recording and analysis.

• variables data

• attributes data

• categorical data

• special data

Quantitative data, where measurements are used for analysis.

• variables data

• attributes data

• categorical data

• special data

A graphic representation of a characteristic of a process, showing plotted values of some statistic gathered from that characteristic, a centerline, and one or two control limits.

• variable chart

• attribute chart

• trend chart

• control chart

A source of variation that affects all the individual values of the process output being studied

• special cause

• common cause

• natural cause

• root cause

A source of variation that affects only some of the output of the process; signaled by one or more points beyond the control limits or a non-random pattern of points within the control limits.

• special cause

• common cause

• natural cause

• root cause

A way of describing the output of a stable system of variation, in which individual values as a group form a pattern that can be described in terms of its location, spread, and shape.

• distribution

• shape

• bell curve

• symmetry

A continuous, symmetrical, bell-shaped frequency distribution for variable data that is the basis for the control charts for variables.

• chi square distribution

• poisson distribution

• binomial distribution

• normal distribution

A discrete probability distribution for attributes data that applies to nonconformities and underlies the c and u control charts.

• chi square distribution

• poisson distribution

• binomial distribution

• normal distribution