A calibration session is a scheduled meeting where reviewers, annotators, moderators, or QA analysts score or label the same sample independently, then compare results and talk through the differences until they agree on how the guidelines apply. It's the actual event that produces reviewer calibration, which is the ongoing goal of everyone applying the same standard.

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‍Why it matters

Calibration doesn't happen on its own. Without a set time to compare notes, people pick up their own habits, and different pairs settle on slightly different rules of thumb. A session brings the disagreements into the open so the whole team resolves them once, instead of each person finding out separately. Sessions are especially useful after guidelines change or when someone new joins, since that's when interpretations are most likely to split.

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‍How a session typically runs

Everyone scores or labels the same sample without seeing anyone else's answers first. Results get compared item by item, and the group discusses each disagreement against the actual guidelines rather than settling it by majority opinion. The outcome gets written down, either as a clarified guideline or a new example, so the decision doesn't live only in people's memories. An agreement metric measured before and after shows whether the session actually narrowed the gap.

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‍What gets calibrated differs by context

In data labeling, a session usually means labeling the same batch, often including known tricky edge cases. In content moderation, it means scoring the same borderline post against policy. In customer support, it typically means scoring the same recorded call or chat transcript against a QA scorecard. The mechanics are the same everywhere, independent scoring then a structured comparison, only the material being judged changes.