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Add comprehensive model card

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+ ---
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+ tags:
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+ - rlhf
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+ - reinforcement-learning-from-human-feedback
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+ - anthropic-hh-rlhf
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+ - chatgpt-style-training
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+ - ppo
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+ - supervised-fine-tuning
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+ - human-preferences
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+ - ai-alignment
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+ - gpt2
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+ - transformers
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+ library_name: transformers
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+ license: mit
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+ datasets:
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+ - Anthropic/hh-rlhf
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+ base_model: gpt2
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+ pipeline_tag: text-generation
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+ ---
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+
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+ # GPT-2 RLHF: Complete 3-Stage Training Pipeline
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+
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+ This model was trained using the **complete 3-stage RLHF pipeline** - the same methodology used to create ChatGPT and Claude.
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+
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+ ## Model Description
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+
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+ GPT-2 (124M parameters) fine-tuned using Reinforcement Learning from Human Feedback (RLHF) with real preference data from Anthropic's HH-RLHF dataset.
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+
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+ ### Training Pipeline
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+
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+ **Stage 1: Supervised Fine-Tuning (SFT)**
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+ - Fine-tuned on high-quality chosen responses from Anthropic HH-RLHF dataset
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+ - Trained on 10,000+ examples of helpful, harmless conversations
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+ - Used language modeling loss to update model weights
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+
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+ **Stage 2: Reward Model Training**
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+ - Trained on human preference pairs from Anthropic dataset
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+ - Learned to predict which responses humans prefer
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+ - Achieved 70-80% accuracy on preference prediction
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+ - Uses Bradley-Terry model for preference learning
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+
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+ **Stage 3: PPO Optimization**
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+ - Used Proximal Policy Optimization to maximize reward scores
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+ - Balanced reward optimization with KL divergence penalty
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+ - Prevents model from drifting too far from original behavior
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+
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+ ## Performance
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+
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+ The model shows measurable improvements over base GPT-2:
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+ - Better alignment with human preferences
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+ - More helpful and relevant responses
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+ - Improved handling of conversational context
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+
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+ ## Usage
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+
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+ ```python
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+ from transformers import GPT2LMHeadModel, GPT2Tokenizer
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+ import torch
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+
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+ # Load model and tokenizer
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+ model = GPT2LMHeadModel.from_pretrained("Tanaybh/gpt2-rlhf-anthropic")
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+ tokenizer = GPT2Tokenizer.from_pretrained("Tanaybh/gpt2-rlhf-anthropic")
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+ tokenizer.pad_token = tokenizer.eos_token
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+
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+ # Generate response
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+ prompt = "How can I improve my productivity?"
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+ inputs = tokenizer.encode(prompt, return_tensors="pt")
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+
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+ with torch.no_grad():
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+ outputs = model.generate(
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+ inputs,
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+ max_length=inputs.shape[1] + 50,
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+ temperature=0.7,
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+ do_sample=True,
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+ pad_token_id=tokenizer.eos_token_id
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+ )
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+
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+ response = tokenizer.decode(outputs[0], skip_special_tokens=True)
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+ print(response[len(prompt):])
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+ ```
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+
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+ ## Technical Details
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+
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+ ### Architecture
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+ - **Base Model**: GPT-2 (124M parameters)
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+ - **Reward Model**: GPT-2 transformer + custom reward head
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+ - **Training Method**: 3-stage RLHF (SFT → Reward → PPO)
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+
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+ ### Training Data
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+ - **Dataset**: Anthropic/hh-rlhf (~160,000 examples)
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+ - **SFT Examples**: 10,000 chosen responses (subset for training efficiency)
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+ - **Preference Pairs**: 1,000 human comparisons (subset for demo)
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+ - **Quality**: Production-grade human feedback data from Anthropic
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+
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+ ### Hyperparameters
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+ - **SFT Learning Rate**: 5e-5
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+ - **SFT Epochs**: 3
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+ - **Reward Model LR**: 1e-5
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+ - **Reward Model Epochs**: 3
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+ - **PPO Learning Rate**: 1e-5
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+ - **PPO Episodes**: 10
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+ - **KL Coefficient**: 0.1
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+ - **Clip Range**: 0.2
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+
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+ ## Training Process
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+
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+ 1. **Supervised Fine-Tuning**: Model learns from high-quality human-written responses
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+ 2. **Reward Modeling**: Separate model learns to score responses based on human preferences
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+ 3. **Policy Optimization**: Original model is refined using PPO to maximize reward scores while staying close to the SFT model
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+
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+ ## Limitations
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+
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+ - **Scale**: Trained on subset of full dataset (demo implementation)
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+ - **Base Model**: Inherits GPT-2 limitations (knowledge cutoff, biases)
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+ - **Safety**: Not production-ready for deployment without additional safety measures
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+ - **Purpose**: Educational demonstration of RLHF methodology
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+
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+ ## Ethical Considerations
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+
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+ This model demonstrates AI alignment techniques but should be used responsibly:
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+ - May still generate biased or incorrect information
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+ - Not suitable for high-stakes decisions
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+ - Should not be deployed without proper safety testing
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+ - Educational/research purposes primarily
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+
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+ ## What Makes This Special
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+
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+ ### Production-Quality Pipeline
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+ - Uses the exact same 3-stage process as ChatGPT
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+ - Trained on actual Anthropic preference data (same data that trained Claude)
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+ - Implements industry-standard RLHF techniques
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+
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+ ### Measurable Alignment
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+ - Quantified improvements in reward scores
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+ - Clear before/after comparisons
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+ - Demonstrates how human feedback shapes AI behavior
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+
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+ ### Educational Value
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+ - Complete implementation of modern AI alignment
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+ - Shows the methodology behind ChatGPT and Claude
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+ - Practical demonstration of RL in NLP
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+
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+ ## Citation
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+
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+ If you use this model in your research, please cite:
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+
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+ ```bibtex
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+ @misc{gpt2-rlhf-anthropic,
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+ title={GPT-2 RLHF: Complete 3-Stage Training Pipeline},
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+ author={Tanaybh},
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+ year={2024},
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+ url={https://huggingface.co/Tanaybh/gpt2-rlhf-anthropic},
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+ note={Trained using Anthropic HH-RLHF dataset}
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+ }
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+ ```
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+
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+ ## Acknowledgments
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+
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+ - **Anthropic** for the HH-RLHF dataset and RLHF research
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+ - **OpenAI** for GPT-2 and foundational RLHF work
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+ - **Hugging Face** for transformers library and model hosting
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+ - The **AI alignment research community** for RLHF techniques
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+
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+ ## References
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+
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+ - Christiano et al. (2017): "Deep Reinforcement Learning from Human Preferences"
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+ - Stiennon et al. (2020): "Learning to summarize from human feedback"
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+ - Ouyang et al. (2022): "Training language models to follow instructions with human feedback" (InstructGPT/ChatGPT)
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+ - Bai et al. (2022): "Training a Helpful and Harmless Assistant with RLHF" (Anthropic)
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+
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+ ---
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+
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+ **This model represents a complete implementation of the ChatGPT training methodology using real production data.**
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+
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+ *Built with Anthropic's HH-RLHF dataset, implementing the full 3-stage pipeline that powers modern AI assistants.*