ZipIt! Merging Models from Different Tasks without Training
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Abstract (arXiv)
Typical deep visual recognition models are capable of performing the one task they were trained on. In this paper, we tackle the extremely difficult problem of combining distinct models with different initializations, each solving a separate task, into one multi-task model without any additional training. Prior work in model merging permutes one model to the space of the other then averages them together. While this works for models trained on the same task, we find that this fails to account for the differences in models trained on disjoint tasks. Thus, we introduce "ZipIt!", a general method for merging two arbitrary models of the same architecture that incorporates two simple strategies. First, in order to account for features that aren't shared between models, we expand the model merging problem to allow for merging features within each model by defining a general "zip" operation. Second, we add support for partially zipping the models up until a specified layer, naturally creating a multi-head model. We find that these two changes combined account for 20-60% improvement over prior work, making it more feasible to merge models trained on disjoint tasks without retraining.
Key facts. Cited by 178 papers in the map (data through 7 Oct 2026). Builds on 56 of its 77 references that are in the map. First posted on arXiv 4 May 2023.
Builds on
56 of 77 references.
References · 56
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Citing papers per year: 2023: 21; 2024: 59; 2025: 58; 2026: 40.
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12 most cited of 156 All 156 (JSON)
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- 2026CORAM: Coherent Orthogonal Rotation for Model Merging18 Aug 2026
- 2026When Do Task Vectors Interfere? Mapping the Validity Boundaries of Weight-Space Composition10 Aug 2026
- 2026Training-Free Knowledge Transfer Across Model Scales through Activation-Guided Pruning31 Jul 2026
- 2026A Survey on the Green Development of Large Models: From Resource-Efficient Architectures to Hardware-Software Co-Design10 Jul 2026
- 2026Signed-Permutation Coordinate Transport for RMSNorm Transformers30 Jun 2026
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- 2026GFFMERGE: Efficient Merging of Graph Neural Force Fields and Beyond2 Jun 2026
12 newest of 156 All 156 (JSON)