Abstract:

This paper is in the nature of a progress report since the author's previous contribution at the ESOMAR Congress of 1966. It starts from the premise that profits on repeat-purchase consumer products can often be increased substantially by substituting cheaper alternatives for one or more of the basic ingredients in the product, while maintaining sales. Another way of putting this, in these days of continuing cost inflation, is to say that the manufacturer can hold consumer prices steady in the face of rising materials costs). In such cases, the manufacturer will usually aim to make a product which is as near as possible indistinguishable from his current product. To this end he will generally want to pre-test the new variant, to ensure that a sufficiently small proportion of his existing users would adversely notice the change if he made it. The author has learned a lot more about such "discrimination tests" since 1966 and this paper summarises lessons which other researchers may find useful, in the areas of research design, procedures and interpretation.