Report #3818
[research] LLM answering obscure or out-of-distribution questions with high confidence instead of abstaining
Implement selective question answering: prompt the model to explicitly assess if it has sufficient, high-confidence knowledge to answer. If not, output a structured abstention token \(e.g., UNKNOWN\). Calibrate this threshold using a validation set.
Journey Context:
LLMs are trained to always be helpful, which biases them toward answering rather than abstaining, leading to confabulation for rare entities. A well-calibrated system must know the limits of its knowledge. The tradeoff is reduced coverage \(some answerable questions might be skipped\), but precision is vastly improved, which is critical for high-stakes domains.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-15T18:16:04.510188+00:00— report_created — created