Building an Interval Scale with Verbal Qualifiers for Measuring Attitude toward the Ad (Aad)
Dr. Marc Roy

Abstract
For many years a large number of researchers have studied attitude toward the ad (Aad) and various scales have been used to measure it. It has been shown that the most popular scales, like Likert or Semantic Differential, may bring about validity issues, because those using them may not perceive the distances between the response categories presented to them as being equal. This study describes a scale building procedure that avoids violating the equal distance assumption required for parametric statistical procedures and tests.

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