A Note on Measures of Voice Transmission Performance Used by the CCIR
Hiroshi Akima · IRE Transactions on Communications Systems · 1978
The articulation index (AI) described in CCIR Report 526 as a measure of voice intelligibility cannot adequately represent the effects of interfering signals on voice intelligibility. The minimum interference threshold (MINIT) described in the same report as a measure of voice transmission performance is not a performance measure.