OpenChat: Advancing Open-source Language Models with Imperfect Data
OpenChat is a collection of open-source language models, optimized and fine-tuned with a strategy inspired by offline reinforcement learning. We use approximately 80k ShareGPT conversations, a conditioning strategy, and weighted loss to deliver outstanding performance, despite our simple approach. Our ultimate goal is to develop a high-performance, commercially available, open-source large language model, and we are continuously making strides towards this vision.
🤖 Ranked #1 among all open-source models on AgentBench
🔥 Ranked #1 among 13B open-source models | 89.5% win-rate on AlpacaEval | 7.19 score on MT-bench
🕒 Exceptionally efficient padding-free fine-tuning, only requires 15 hours on 8xA100 80G
To use these models, we highly recommend installing the OpenChat package by following the installation guide and using the OpenChat OpenAI-compatible API server by running the serving command from the table below. The server is optimized for high-throughput deployment using vLLM and can run on a GPU with at least 48GB RAM or two consumer GPUs with tensor parallelism. To enable tensor parallelism, append --tensor-parallel-size 2 to the serving command.
When started, the server listens at localhost:18888 for requests and is compatible with the OpenAI ChatCompletion API specifications. See the example request below for reference. Additionally, you can access the OpenChat Web UI for a user-friendly experience.
To deploy the server as an online service, use --api-keys sk-KEY1 sk-KEY2 ... to specify allowed API keys and --disable-log-requests --disable-log-stats --log-file openchat.log for logging only to a file. We recommend using a HTTPS gateway in front of the server for security purposes.
Example request (click to expand)
bash
1curl http://localhost:18888/v1/chat/completions \2 -H "Content-Type: application/json"\3 -d '{
4 "model": "openchat_v3.2",
5 "messages": [{"role": "user", "content": "You are a large language model named OpenChat. Write a poem to describe yourself"}]
6 }'
We have evaluated our models using the two most popular evaluation benchmarks **, including AlpacaEval and MT-bench. Here we list the top models with our released versions, sorted by model size in descending order. The full version can be found on the MT-bench and AlpacaEval leaderboards.
To ensure consistency, we used the same routine as ChatGPT / GPT-4 to run these benchmarks. We started the OpenAI API-compatible server and set the openai.api_base to http://localhost:18888/v1 in the benchmark program.
Model
Size
Context
Dataset Size
💲Free
AlpacaEval (win rate %)
MT-bench (win rate adjusted %)
MT-bench (score)
v.s. text-davinci-003
v.s. ChatGPT
GPT-4
1.8T*
8K
❌
95.3
82.5
8.99
ChatGPT
175B*
4K
❌
89.4
50.0
7.94
Llama-2-70B-Chat
70B
4K
2.9M
✅
92.7
60.0
6.86
OpenChat 3.2 SUPER
13B
4K
80K
✅
89.5
57.5
7.19
Llama-2-13B-Chat
13B
4K
2.9M
✅
81.1
55.3
6.65
WizardLM 1.2
13B
4K
196K
✅
89.2
53.1
7.05
Vicuna 1.5
13B
2K
125K
✅
78.8
37.2
6.57
*: Estimated model size
**: The benchmark metrics represent a quantified measure of a subset of the model's capabilities. A win-rate greater than 50% does not necessarily indicate that the model is better than ChatGPT in all scenarios or for all use cases. It is essential to consider the specific tasks or applications for which the model was evaluated and compare the results accordingly.
Limitations
Foundation Model Limitations
Despite its advanced capabilities, OpenChat is still bound by the limitations inherent in its foundation models. These limitations may impact the model's performance in areas such as:
Complex reasoning
Mathematical and arithmetic tasks
Programming and coding challenges
Hallucination of Non-existent Information
OpenChat may sometimes generate information that does not exist or is not accurate, also known as "hallucination". Users should be aware of this possibility and verify any critical information obtained from the model.
@article{wang2023openchat,
title={OpenChat: Advancing Open-source Language Models with Mixed-Quality Data},
author={Wang, Guan and Cheng, Sijie and Zhan, Xianyuan and Li, Xiangang and Song, Sen and Liu, Yang},
journal={arXiv preprint arXiv:2309.11235},
year={2023}
}