Optimal use of the visual analog scale: Observations from ratings of emotional speech

Abstract

Researchers use many tools to measure participant performance during experiments. The visual analog scale has been used in many areas of research as a valid way to measure listener perception of various aspects of a signal. Ratings using the visual analog scale are commonly averaged over a number of trials to estimate listeners’ perception. This presentation delves into issues which may be encountered when using a visual analog scale for measuring perception of voice (in this case, vocal emotion). An experiment was performed which gathered ratings of emotional activation and pleasantness for many stimuli of four emotion categories (angry, sad, happy, and calm) from 10 listeners. These data will be examined for patterns of variance in a time-course analysis to identify listener certainty or biases created when using the visual analog scale during a long experimental task. Implications of bias and the impact on research results will be discussed along with additional and alternative measurement options for researchers to consider.