Quality of goods and services is important to all customers. Therefore the person who takes responsibility for assuring the quality is critical to both the organisation and its customers. In many professional firms it might be a senior partner while in many large manufacturing companies it might be a senior engineer. Often the role of that person is to ensure that standards and specifications are met.
It may be a surprise to some that statisticians are increasingly filling this role of providing quality assurance. The reason is simple, reducing variation in a product or service is often the most cost effective way of reliably meeting specifications. Understanding variation is the key to this and is also the statistician's chief skill. It is perhaps not surprising that many of the prominent names in the quality movement - Shewart and Deming to name just two - described themselves primarily as statisticians.
Many of the techniques in wide use in quality assurance are basically statistical but have been simplified for use by non-statisticians. These include such tools as control charts and histograms. However an experienced statistician has the greater depth of understanding to handle the unexpected and to take advantage of unusual situations.
An example of this is a recent project where, as statisticians, Data Analysis Australia provided certification for a reference material, or standard, to be used by mineral laboratories as a part of their own quality assurance procedures. These mineral standards are a critical product of our client, Western Mineral Standards, with laboratories around the world using them to calibrate their results, in this case for measuring gold concentrations in mineral samples. Several standards were being developed simultaneously and as this was a new subsidiary and area of business for Western Refractories, extra care had to be taken in the review of the processes used to ensure uniformity of product.