Speech intelligibility indexes average signal-to-noise ratio across critical bands
Evidence
If that were not enough, he also made substantial contributions to our knowledge of speech perception and developed a tool (originally called the Articulation Index, now revised to the Speech Intelligibility Index [SII]) that allows one to calculate the amount of speech information available in different frequency bands. The SII is able to robustly predict intelligibility scores for certain speech materials and acoustic environments (ANSI- 3.5, 2017) and is now used in industrial applications and to assess the impact of hearing loss on speech perception. — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 90
Categorization
- DEFINE: Defines SII (formerly Articulation Index), a working predictive model the reader explicitly wants as a concept for assessing hearing loss impact.
- XREF: The Speech Intelligibility Index is a predictive model directly usable in audiology practice, connects to any later chapter on speech perception and hearing-aid fitting. — connects to: The range of SNRs contributing to speech intelligibility is wider than SII standards assume; Speech intelligibility models need nonlinear SNR-importance functions for filtered sources; Speech intelligibility can be predicted by measuring signal envelope modulation decay (+5 more)
- corroborated: 2 independent passages support this claim — Jennifer Lentz, Psychoacoustics- Perception of Normal…, 90