Signal-to-Noise Ratio.

Similar to ‘Interference Effects’, this is a measure of how much relevant to irrelevant content you have on a page. More ‘signal’ and less ‘noise’ is better.

Robust Parameter DesignReliaWiki
Taguchi Methods: Robust Design Experiments - Signal-to-Noise (S/N) RatiosStatistica
Designing for NoiseUX BoothNovember 23rd, 2010
What the Word “Minimalist” MeansUX MovementJuly 24th, 2010
What’s The Signal to Noise Ratio Of Your Design?Vanseo DesignApril 26th, 2010