Mid-level interview questionAsked at Mercor · interview write-up
You're handed a noisy dataset for LLM post-training. How do you decide whether it helps, and what evidence would you show?
Model answer
Treat it as an experiment. Fix the base model, recipe and a held-out eval suite for target skills plus general regressions. Train three runs: without the data, with it raw, and with it filtered, say by deduplication, a judge or reward-model score, and removing items that overlap the evals. Show the deltas with confidence intervals, over a few seeds if you can, broken down by slice. The evidence is a clean ablation, not hand-picked examples.
Practise the rest
20 Fine-tuning & alignment questions, 492 in all, each with a model answer. Free.
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