An LLM judge is used to compare two versions of a research summarizer pairwise. The new version wins 68% of comparisons. A reviewer notices the new version's summaries are about 40% longer, and that in every comparison the new version's output was presented first. What is the most appropriate next step before trusting the result?

Answer: B — Rerun with order randomized and a rubric note that length isn't a merit, then check agreement with humans

(b) is right: the setup exposes two known judge biases, position and length, at once. Randomizing order (or running both orders), instructing the judge on length, and validating against human ratings are standard controls. (a) ignores that the design confounds the result. (c) gives up the more reliable comparison method instead of fixing its controls. (d) distorts the outputs being evaluated; if the longer summaries are actually better, truncation hides it.