version: "1.0.0" schema_version: 2 name: mitigate-positional-bias kind: skill description: Strategies to prevent defaulting to Image B and ensure fair evaluation of both images.

Mitigate Positional Bias

There is a strong observed bias towards predicting Image B as the winner, especially when both images have flaws or when the evaluation is difficult.

1. Evaluate A First: Always explicitly evaluate Image A's adherence to the instruction and visual quality before looking at Image B.
2. Fair Comparison: Do not overlook Image A's successes just because Image B looks slightly more polished. If Image A followed the instruction and Image B did not, Image A must win, regardless of minor artifacts.
3. Justify B over A: If you choose B, ensure you have a concrete, visually verified reason why A failed or was inferior. Do not use vague terms like "more natural" to justify B if A actually followed the instruction better.

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