At Datasaur, we are committed to providing our users with cutting-edge solutions for their annotation needs. We are thrilled to announce the release of a new supported algorithm for calculating Inter-Annotator Agreement (IAA): Krippendorff's Alpha. While we have previously supported IAA calculations using Cohen's Kappa, the addition of Krippendorff's Alpha offers a robust alternative, widening the scope of applications for our users. In this blog post, we will explore the unique features of Krippendorff's Alpha and illustrate the conditions under which it excels, compared to Cohen's Kappa.
Before delving into the specifics of Krippendorff's Alpha, it's important to understand the concept of Inter-Annotator Agreement. IAA measures the level of agreement between multiple annotators when labeling the same data. High agreement indicates consistency and reliability in annotations, while low agreement signals discrepancies that might require further investigation or clarification.
In Datasaur, the IAA will be calculated when a project status is changed to Ready for Review (all labelers mark the project as complete) or Complete (a reviewer marks the project as complete).
Both Cohen's Kappa and Krippendorff's Alpha are widely used metrics for IAA calculation, but they operate under different assumptions and are suited for different types of data and annotation tasks.
With the introduction of Krippendorff's Alpha, Datasaur empowers users to assess Inter-Annotator Agreement with greater precision and flexibility. Whether your annotation task involves multiple categories, ordinal data, or complex annotation schemes, Krippendorff's Alpha provides a reliable metric to gauge annotator agreement. Moreover, you can now compare the calculation between Cohen’s Kappa and Krippendroff’s Alpha, making it easier to find the most suitable calculation for your labeling process.