5.36 - Pareto Analysis

Key Points

In order to determine what needs to be analysed we use a technique called Pareto Analysis. This enables us to rank our problems according to the so called 80-20 rule. A typical list of faults is shown in the diagram below that identifies issues with paint quality.

This chart reveals the most frequent problems with paint finish. But we need to know how difficult or costly they are to fix or re-work. The next chart displays that information.

The order of priority has changed when we examine things from a more relevant perspective. Another way would be to measure what was important to the end user or customer (customer Critical to Quality (CTQ)). This may reveal another set of measures for which we could conduct a similar analysis. The customer ranking of the paint problems maybe different to ours and that has got be considered also.

There also maybe correlation between some of the factors which will have to be considered. If correlations can be established then the number of factors measured could be reduced. If some problems were difficult to measure and it was found to correlate to another more easily measured factor, it would make sense to plot the easy one and map to the other by whatever the correlation factor is.

Other Resources

The Society of Motor Manufacturers and Traders (SMMT) produce a number of excellent and more detailed guidelines on SPC, including Pareto.

SMMT Business Improvement Guides