This book presents a new diagnostic information methodology to assess
the quality of conversational telephone speech. For this, a conversation
is separated into three individual conversational phases (listening,
speaking, and interaction), and for each phase corresponding perceptual
dimensions are identified. A new analytic test method allows gathering
dimension ratings from non-expert test subjects in a direct way. The
identification of the perceptual dimensions and the new test method are
validated in two sophisticated conversational experiments. The dimension
scores gathered with the new test method are used to determine the
quality of each conversational phase, and the qualities of the three
phases, in turn, are combined for overall conversational quality
modeling. The conducted fundamental research forms the basis for the
development of a preliminary new instrumental diagnostic conversational
quality model. This multidimensional analysis of conversational
telephone speech is a major landmark towards deeply analyzing
conversational speech quality for diagnosis and optimization of
telecommunication systems.