The current state of the PEFT docs is not one of structure and I was constantly annoyed that whenever I wanted to change something there were several places that needed touching and they all felt disconnected. So this is my attempt at structuring the docs. Some of these ideas are quite old (discussed in 01/2025) but are still valid. I've removed most of the code guides without replacement. That's not ideal, I think we should have code examples but I'm think they should be method-focused. Maybe one general example of a training workflow is sufficient because most methods follow the same scheme. All details from the method guides (prompting, lora, oft/boft, etc.) are now integrated into the respective method pages instead. I would have hesitated to do this if these guides would have integrated information about the adapters but they didn't. I think it makes a lot more sense to have one place for each method to gather examples/tips/recommendations and that is now the `package_refernce/<method>` page. This page now also hosts a small space that shows the MetaMathQA (and potentially other) benchmark results highlighted for that method. I've moved the LoRA initializations to `package_reference/lora#Initialization` and converted the init methods to `<hfoption>`-tags. This collapses them to a list but may reduce searchability through the document - at least firefox is not able to search 'through' the option tabs. This also doesn't make them appear in the ToC and people specifically searching for, say, PiSSA won't find it directly. I think that's OK though, since the search is able to locate it. The quicktour is a bit more detailed about what happens under the hood (quick doesn't have to mean simplistic) and includes some new visualizations. I hope that we can integrate more visualizations in the future where it makes sense. * Remove PEFT method space + front page buttons The space was not that useful anymore since most methods are compatible with most models. The front page buttons are, at least temporarily, with the exception of the quicktour and method overview buttons. I like the visuals but there should only be elements that are useful. --------- Co-authored-by: Benjamin Bossan <BenjaminBossan@users.noreply.github.com> Co-authored-by: Steven Liu <59462357+stevhliu@users.noreply.github.com>
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Context-aware Prompt Tuning: Advancing In-Context Learning with Adversarial Methods
CPT optimizing only specific token embeddings while keeping the rest of the model frozen (image source).Context-Aware Prompt Tuning (CPT) is designed to enhance few-shot classification by refining only context embeddings. This approach combines ideas from In-Context Learning (ICL), Prompt Tuning (PT), and adversarial optimization, focusing on making model adaptation both parameter-efficient and effective. In CPT, only specific context token embeddings are optimized, while the rest of the model remains frozen. To prevent overfitting and maintain stability, CPT uses controlled perturbations to limit the allowed changes to context embeddings within a defined range. Additionally, to address the phenomenon of recency bias—where examples near the end of the context tend to be prioritized over earlier ones—CPT applies a decay loss factor.
The abstract from the paper is:
Large Language Models (LLMs) can perform few-shot learning using either optimization-based approaches or In-Context Learning (ICL). Optimization-based methods often suffer from overfitting, as they require updating a large number of parameters with limited data. In contrast, ICL avoids overfitting but typically underperforms compared to optimization-based methods and is highly sensitive to the selection, order, and format of demonstration examples. To overcome these challenges, we introduce Context-aware Prompt Tuning (CPT), a method inspired by ICL, Prompt Tuning (PT), and adversarial attacks. CPT builds on the ICL strategy of concatenating examples before the input, extending it by incorporating PT-like learning to refine the context embedding through iterative optimization, extracting deeper insights from the training examples. Our approach carefully modifies specific context tokens, considering the unique structure of the examples within the context. In addition to updating the context with PT-like optimization, CPT draws inspiration from adversarial attacks, adjusting the input based on the labels present in the context while preserving the inherent value of the user-provided data. To ensure robustness and stability during optimization, we employ a projected gradient descent algorithm, constraining token embeddings to remain close to their original values and safeguarding the quality of the context. Our method has demonstrated superior accuracy across multiple classification tasks using various LLM models, outperforming existing baselines and effectively addressing the overfitting challenge in few-shot learning.
Take a look at Example for a step-by-step guide on how to train a model with CPT.
Benchmark overview
There is no benchmark for this method yet. Feel free to contribute an experiment configuration but make sure to first create an issue here.
API
CPTConfig
autodoc tuners.cpt.config.CPTConfig
CPTEmbedding
autodoc tuners.cpt.model.CPTEmbedding
