Pareto Chart Analyses

The Pareto chart analysis is a simple but powerful way of identifying the causes of quality problems or loss. It amounts to constructing a histogram of the number of quality problems or loss by some meaningful units, for example, by type of problem or division within the company.

According to the so-called Pareto principle, the majority of the quality loss is caused by a small number of factors. Put another way, in many cases, a few types of problems often cause the majority of quality loss, or a few divisions within the company may produce the majority of loss. Such "maldistribution" (uneven distribution) of quality loss is very common, and can easily be detected via the Pareto chart.

The Pareto chart is described in most standard quality control textbooks; see for example, Hart and Hart (1989), Juran (1962), Juran and  Gryna (1970), Montgomery (1985, 1991), Pyzdek (1989), or Vaughn (1974).

See also, Quality Control.