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Fixed-choice decision models select an answer in one forward pass

nishtahir.com 4 min read Editor score 7/10

The approach masks all but a fixed set of answer tokens and picks the highest-probability option in one pass, instead of generating a constrained response token by token. This can make structured, fixed-option answers faster to produce.

What
A fixed-choice decision model selects among predefined answers in one forward pass instead of generating a multi-token response.
How
It masks all but allowed option tokens, then chooses the highest-probability token; the resulting scores are not necessarily calibrated answer probabilities.
Why it matters
Single-pass selection can avoid repeated decoding for fixed-choice outputs, while engineers should not treat raw token confidence as correctness probability.
input produces mask to optio… softmax highest proba… prompt model logits option tokens probabilities prediction
Constrained decoding turns a prompt into a prediction from a fixed set of options. Sketched from the article's own text.

Read on nishtahir.com → Hacker News · 58 comments

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