Mean Opinion Score scales standardize audio-quality evaluation on a 1-to-5 range

Evidence

The user interface normally contains a numerical scale, which is assumed to help the subject to describe the auditory attribute being studied. The numerical scaling of an auditory event is often performed on a scale with easily conceivable numbers, such as pi ∈[1, 5], pi ∈[1, 10] or pi ∈[0, 100]. A special case is the Mean Opinion Score (MOS) scale, MOS ∈[1, 5], which is commonly used to evaluate audio quality. A verbal description may correspond to different positions on the scale, for example, the value 5 may correspond to ‘excellent’ quality. — Ville Pulkki, Matti Karjalainen, Communication Acoustics- An…, 902

Categorization

• DEFINE: Defines MOS scale and its use in evaluating audio quality.
• ADDENDUM: Relates to practical audio evaluation — a concrete methodological baseline for user-experience measurement.