We carried out two experiments to investigate how the shading of the options in a response scale affected the answers to the survey questions. The experiments were embedded in two web surveys, and they varied whether the two ends of the scale were represented by shades of
the same or different hues. The experiments also varied the numerical labels for the scale points and examined responses to both unipolar scales (assessing frequency) and bipolar scales (assessing favorability). We predicted that the use of different hues would affect how respondents viewed the low end of the scale, making responses to that end seem more extreme than when the two ends were shades of the same hue. The results were generally consistent with this prediction. When the end points of the scale were shaded in different hues, the responses tended toward shift to the high end of the scale.