Papers › PICARD: Parsing Incrementally for Constrained Auto-Regressive Decoding from Language Models
PICARD: Parsing Incrementally for Constrained Auto-Regressive Decoding from Language Models
Torsten Scholak, Nathan Schucher, Dzmitry Bahdanau
Large pre-trained language models for textual data have an unconstrained output space; at each decoding step, they can produce any of 10,000s of sub-word tokens. When fine-tuned to target constrained formal languages like SQL, these models often generate invalid code, rendering it unusable. We propose PICARD (code and trained models available at https://github.com/ElementAI/picard), a method for constraining auto-regressive decoders of language models through incremental parsing. PICARD helps to find valid output sequences by rejecting inadmissible tokens at each decoding step. On the challenging Spider and CoSQL text-to-SQL translation tasks, we show that PICARD transforms fine-tuned T5 models with passable performance into state-of-the-art solutions.
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Code Syntology ran Syntology
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Tasks
1 archive task tag without a task page not shown.
Results from the paper archive 2025-07-28
| Task | Dataset | Model | Metric | Value | Rank at snapshot | Leaderboard | Report |
|---|---|---|---|---|---|---|---|
| Dialogue State Tracking | CoSQL | T5-3B + PICARD | interaction match accuracy | 23.7 | #2 of 9 | Archive leaderboard | report |
| Dialogue State Tracking | CoSQL | T5-3B + PICARD | question match accuracy | 54.6 | #2 of 9 | Archive leaderboard | report |
| Semantic Parsing | spider | T5-3B + PICARD | Accuracy | 71.9 | #5 of 10 | Archive leaderboard | report |
| Text-To-SQL | SPIDER | T5-3B+PICARD | Exact Match Accuracy (in Dev) | 75.5 | #1 of 4 | Archive leaderboard | report |
| Text-To-SQL | SPIDER | T5-3B+PICARD | Execution Accuracy (in Dev) | 79.3 | #1 of 4 | Archive leaderboard | report |
| Text-To-SQL | SPIDER | T5-3B | Exact Match Accuracy (in Dev) | 71.5 | #4 of 4 | Archive leaderboard | report |
| Text-To-SQL | SPIDER | T5-3B | Execution Accuracy (in Dev) | 74.4 | #4 of 4 | Archive leaderboard | report |
| Text-To-SQL | spider | T5-3B + PICARD | Exact Match Accuracy (Dev) | 75.5 | #12 of 20 | Archive leaderboard | report |
| Text-To-SQL | spider | T5-3B + PICARD | Exact Match Accuracy (Test) | 71.9 | #12 of 20 | Archive leaderboard | report |
| Text-To-SQL | spider | T5-3B + PICARD | Execution Accuracy (Test) | 75.1 | #12 of 20 | Archive leaderboard | report |
Ranks are positions in the archive's leaderboards as they stood at the 2025-07-28 snapshot. Results published since then are not among these rows, so a rank here is not a current standing.
Methods
Introduced by this paper: PICARD
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