What is Prompt Tuning?

IBM Technology
16 Jun 202308:33

TLDRPrompt tuning is an energy-efficient technique for adapting large language models (LLMs) to specialized tasks without the need for extensive retraining. Unlike fine-tuning, which requires gathering thousands of labeled examples, prompt tuning uses front-end prompts to provide task-specific context. These prompts can be human-generated or AI-generated embeddings that guide the model towards the desired prediction. Prompt engineering involves creating such prompts, but recent advancements have led to the use of AI-designed 'soft prompts' that outperform human-engineered 'hard prompts'. Soft prompts are effective but lack interpretability, making them opaque. Prompt tuning is revolutionizing multitask learning and continual learning, allowing for faster and more cost-effective model specialization.

Takeaways

  • 🤖 Large Language Models (LLMs) like ChatGPT are flexible foundation models trained on vast internet data and can perform various tasks.
  • 🔍 To improve LLMs for specialized tasks, 'fine tuning' was traditionally used, requiring a large set of labeled examples.
  • 🌟 'Prompt tuning' is a newer, energy-efficient technique that allows tailoring LLMs to specific tasks with limited data.
  • 📝 In prompt tuning, task-specific context is given to the model through cues or prompts, which can be human-introduced words or AI-generated embeddings.
  • 🔑 Prompt engineering involves creating prompts that guide LLMs to perform specialized tasks, like an English to French translator.
  • 💡 Prompts prime the model to retrieve appropriate responses from its vast memory, such as translating words into French.
  • 🚀 'Soft prompts', AI-designed embeddings, have been shown to outperform human-engineered 'hard prompts' and are used in prompt tuning.
  • 📉 One drawback of prompt tuning and soft prompts is the lack of interpretability; the AI can't explain why it chose certain embeddings.
  • 🛠️ Prompt tuning allows for faster adaptation to specialized tasks compared to fine tuning and prompt engineering, useful for multitask learning and continual learning.
  • ♻️ Universal prompts in multitask prompt tuning enable models to switch between tasks quickly and at a lower cost than retraining.
  • 🔄 Prompt tuning is a game changer, making it easier to adapt models to new tasks and fix problems without extensive retraining.

Q & A

  • What is a foundation model?

    -A foundation model is a large, reusable model that has been trained on vast amounts of knowledge on the Internet, and is designed to be flexible for various tasks such as analyzing legal documents or writing poems.

  • What is the primary method to improve the performance of pre-trained Large Language Models (LLMs) for specialized tasks before the advent of prompt tuning?

    -The primary method was 'fine tuning', which involves gathering and labeling a large number of examples of the target task and then fine-tuning the model with these examples rather than training a new model from scratch.

  • How does prompt tuning differ from fine tuning?

    -Prompt tuning allows a company with limited data to tailor a massive model to a very narrow task without the need for gathering thousands of labeled examples as in fine tuning. It uses task-specific context provided by prompts to guide the model towards the desired decision or prediction.

  • What are the two types of prompts used in prompt engineering?

    -The two types of prompts are 'hard prompts', which are hard-coded by a human, and 'soft prompts', which are AI-designed embeddings that outperform human-engineered prompts.

  • What is the main challenge with using soft prompts in prompt tuning?

    -The main challenge is the lack of interpretability. Soft prompts are optimized for a given task, but the AI often cannot explain why it chose those specific embeddings, making them opaque.

  • How does prompt engineering work for a specialized task like language translation?

    -Prompt engineering involves creating a prompt that guides the LLM to perform the specialized task. For language translation, the engineer might start with a prompt like 'translate English to French' and provide short example translations to guide the model.

  • What is the difference between prompt engineering and prompt tuning?

    -Prompt engineering involves manually creating prompts to guide the model, while prompt tuning uses AI-generated soft prompts that are embedded into the model to guide it towards the desired output without manual intervention.

  • Why is prompt tuning considered more energy efficient than fine tuning?

    -Prompt tuning is more energy efficient because it does not require the gathering and labeling of thousands of examples or the retraining of the model, which can be computationally intensive.

  • In what areas is prompt tuning proving to be a game changer?

    -Prompt tuning is a game changer in areas such as multitask learning, where models need to switch between tasks quickly, and continual learning, where AI models need to learn new tasks without forgetting old ones.

  • What is the role of a prompt engineer?

    -A prompt engineer's role is to develop prompts that guide LLMs to perform specialized tasks effectively. They create the cues or front-end prompts that provide the model with task-specific context.

  • How does prompt tuning help in adapting a model to specialized tasks faster than fine tuning and prompt engineering?

    -Prompt tuning allows for the use of AI-generated soft prompts that can be high level or task-specific, acting as a substitute for additional training data. This enables the model to adapt more quickly and with less computational cost than fine tuning or manual prompt engineering.

  • What is the significance of using embeddings in soft prompts?

    -Embeddings in soft prompts are strings of numbers that distill knowledge from the larger model, providing a way to guide the model towards a desired decision or prediction without needing to understand the human language.

Outlines

00:00

🤖 Introduction to Foundation Models and Prompt Tuning

This paragraph introduces the concept of large language models (LLMs), which are foundation models trained on a vast amount of internet data. It explains their flexibility in performing various tasks like analyzing legal documents or writing poems. The paragraph then explores the concept of 'fine tuning', which involves gathering and labeling numerous examples to improve a model's performance on a specific task. However, it contrasts this with 'prompt tuning', a more energy-efficient method that allows for task-specific tailoring with limited data. Prompt tuning uses cues or prompts to provide context to the model, which can be either human-introduced words or AI-generated numbers in the model's embedding layer. The paragraph also touches on 'prompt engineering', which involves creating prompts to guide LLMs to perform specialized tasks. The speaker expresses interest in becoming a prompt engineer and provides an example of how to engineer a prompt for an English to French language translator. The paragraph concludes with a discussion on the use of 'soft prompts', which are AI-designed and have been shown to outperform human-engineered 'hard prompts'. It notes the drawback of prompt tuning and soft prompts, which is their lack of interpretability.

05:02

📚 Specialization Techniques for Pre-trained Models

The second paragraph delves into three methods for specializing a pre-trained model: fine tuning, prompt engineering, and prompt tuning. Fine tuning involves supplementing the pre-trained model with thousands of examples specific to the task, allowing the model to perform a specialized function. Prompt engineering, on the other hand, involves adding an engineered prompt to the input without altering the pre-trained model, effectively providing two prompts for specialization. Prompt tuning also uses a pre-trained model and an input, but it introduces an AI-generated 'soft prompt' to guide the model towards a specialized task. The paragraph highlights the advantages of prompt tuning, such as its ability to quickly adapt models for multitask learning and continual learning, making it more efficient than the other two methods. The speaker humorously reflects on the potential impact of AI-generated soft prompts on the future of prompt engineering careers, suggesting a shift towards working with embeddings and numerical representations of knowledge.

Mindmap

Keywords

💡Foundation models

Foundation models refer to large, pre-trained models that have been developed using vast amounts of data from the internet. These models are flexible and can perform a wide range of tasks, such as analyzing legal documents or creating poetry. In the context of the video, foundation models are the starting point for further specialization through techniques like fine tuning or prompt tuning.

💡Fine tuning

Fine tuning is a method used to improve the performance of pre-trained Large Language Models (LLMs) for a specific task. It involves gathering and labeling numerous examples of the target task and then adjusting the pre-trained model to better perform that task. The video explains that fine tuning requires a significant amount of data and computational resources.

💡Prompt tuning

Prompt tuning is an energy-efficient technique that allows for the customization of a large pre-trained model for a specialized task without the need for extensive data collection. It involves feeding the model with specific prompts to provide it with task-specific context. The video emphasizes that prompt tuning is a simpler and more efficient alternative to fine tuning.

💡Prompt engineering

Prompt engineering is the process of creating prompts that guide a Large Language Model to perform specialized tasks. It is an art of crafting the right cues to lead the model towards a desired output. In the script, the speaker expresses a desire to become a prompt engineer and demonstrates how to engineer a prompt for an English to French translation task.

💡Soft prompts

Soft prompts are AI-generated prompts that have been shown to outperform human-engineered prompts, also known as hard prompts. Unlike hard prompts that are explicitly crafted by humans, soft prompts consist of embeddings or numerical representations that guide the model towards the desired output. They are used in prompt tuning and are a key component in adapting models to specialized tasks more efficiently.

💡Embedding layer

The embedding layer in the context of the video refers to the part of the AI model where numerical representations (embeddings) are introduced to provide task-specific context to the model. These embeddings are crucial for prompt tuning, as they guide the model towards making a decision or prediction without the need for additional training data.

💡Interpretability

Interpretability in the context of AI refers to the ability to understand and explain the decisions or outputs made by a model. The video points out that one drawback of prompt tuning and soft prompts is the lack of interpretability, meaning that while the AI can find prompts that are optimized for a task, it often cannot explain why those specific embeddings were chosen.

💡Multitask learning

Multitask learning is a field in AI where models are designed to perform multiple tasks simultaneously or quickly switch between tasks. The video discusses how prompt tuning is proving to be beneficial in multitask learning by allowing for the creation of universal prompts that can be easily adapted and reused.

💡Continual learning

Continual learning is an area of AI focused on developing models that can learn new tasks and concepts while retaining knowledge of previously learned information. Prompt tuning is highlighted as a promising technique in this field, as it enables models to adapt to new tasks without forgetting old ones.

💡Hard prompts

Hard prompts are human-engineered prompts that are explicitly designed to guide a Large Language Model towards a specific output. The video contrasts hard prompts with soft prompts, noting that while hard prompts are more recognizable to humans, soft prompts, designed by AI, are often more effective.

💡Energy efficiency

Energy efficiency in the context of the video refers to the reduced computational resources and environmental impact associated with prompt tuning compared to fine tuning. By using prompt tuning, companies can tailor AI models to specific tasks without the need for extensive data gathering and retraining, which saves energy and resources.

Highlights

Prompt tuning is a technique that allows tailoring a pre-trained large language model to a specialized task with limited data.

Unlike fine tuning, prompt tuning does not require gathering thousands of labeled examples.

Prompts provide task-specific context to guide the AI model towards a desired decision or prediction.

Prompt engineering involves developing prompts that guide large language models to perform specialized tasks.

Soft prompts, designed by AI, have been shown to outperform human-engineered prompts known as hard prompts.

Soft prompts consist of embeddings or strings of numbers that distill knowledge from the larger model.

Prompt tuning can be used for multitask learning, where models need to switch between tasks quickly.

Multitask prompt tuning allows the model to be adapted swiftly and at a fraction of the cost of retraining.

Prompt tuning is effective in the field of continual learning, where AI models learn new tasks without forgetting old ones.

Prompt tuning is faster and more efficient than fine tuning and prompt engineering for adapting models to specialized tasks.

One drawback of prompt tuning is the lack of interpretability; AI can't explain why it chose certain embeddings.

Prompt tuning is a game changer in various areas, making it easier to find and fix problems in specialized tasks.

Prompt engineering involves creating a task description and adding short examples to guide the model.

Human-written prompts prime the model to retrieve appropriate responses from its vast memory.

Soft prompts act as a substitute for additional training data and are highly effective in guiding the model.

Prompt tuning can be used to create universal prompts that can be easily recycled for different tasks.

The process of prompt tuning involves using a pre-trained model with an AI-generated soft prompt for specialization.

Prompt tuning is a more energy-efficient technique than fine tuning for improving model performance on specialized tasks.