Mean opinion score (MOS) revisited: methods and applications, limitations and alternatives.

Mean opinion score (MOS) has become a very popular indicator of perceived media quality. While there is a clear benefit to such a 'reference quality indicator' and its widespread acceptance, MOS is often applied without sufficient consideration of its scope or limitations. In this paper, we critically examine MOS and the various ways it is being used today. We highlight common issues with both subjective and objective MOS and discuss a variety of alternative approaches that have been proposed for media quality measurement. [ABSTRACT FROM AUTHOR]