Developing Objective Linear Scale Data from Subjective Tests for Consumer Products

  • Ko, Young Chan ;
  • Park, Jong-Moon
  • Received : 2015.11.13
  • Accepted : 2016.01.15
  • Published : 2016.02.28


In the consumer products industry, it has been highly desirable to develop objective test methods to replace subjective evaluation methods. In developing an objective test method, subjective evaluation data should be on a linear scale. According to Thurstone's theory of comparative judgment, a%-preference from a paired-comparison test can be converted to a linear-scale value. The required number (N) of paired-comparison tests increases dramatically as the number of products increases. This problem should be solved by classifying the total products into several subgroups consisting of 3-4 products in each group. By doing so, it can not only significantly reduce the number of required paired-comparison tests, but it can also obtain more reliable, reproducible data.


Subjective testing;objective testing;linear scale;non-linear;paired-comparison;round-robin test;Thurstone interval scale value;normal deviate


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