Call Center Audio Annotation for Sentiment and Speech Analysis
Annotated 150 hours of English-language customer service calls from telecommunications clients. Performed verbatim transcription with precise timestamps for each utterance. Conducted speaker diarization to distinguish between agents and customers in overlapping dialogues. Labeled emotions including frustration, satisfaction, anger, and neutrality based on vocal cues like pitch changes, volume spikes, and pauses. Flagged non-speech elements such as background noise or hold music that impacted context. Reviewed annotations in batches of 20 calls per day to ensure 98% inter-annotator agreement on sentiment tags.