The forced choice discrimination tests are used to confirm suspected small differences in product characteristics or product quality and to select respondents for discrimination tests. Sometimes discrimination is desirable, such as, with a planned improvement in a product versus the original. Sometimes discrimination is undesirable, such as, a change to a less costly ingredient or when trying to match the paint on a car door to the rest of the automobile after an accident. The tests given here are sensitive methods and, thus, are most applicable when the differences are slight. Paired comparisons and rating scales are more appropriate for large differences. Two major applications are in production quality control and cost reductions.