Large Language Model
PLEX: Making the Most of the Available Data for Robotic Manipulation Pretraining
Thomas, Garrett, Cheng, Ching-An, Loynd, Ricky, Frujeri, Felipe Vieira, Vineet, Vibhav, Jalobeanu, Mihai, Kolobov, Andrey
Transformers [1] have lead to breakthroughs in training large-scale general representations for computer vision (CV) and natural language processing (NLP) [2], enabling zero-shot adaptation and fast finetuning [3]. At the same time, despite impressive progress, transformer-based representations haven't shown the same versatility for robotic manipulation. Some attribute this gap to the lack of suitable training data for robotics [3]. We argue instead that data relevant to training robotic manipulation models is copious but has important structure that most existing training methods ignore and fail to leverage. These insights lead us to propose a novel transformer-based architecture, called PLEX, that is capable of effective learning from realistically available robotic manipulation datasets. We observe that robotics-relevant data falls into three major categories: (1) Video-only data, which contain high-quality and potentially description-annotated demonstrations for an immense variety of tasks but have no explicit action information for a robot to mimic; (2) Data containing matching sequences of percepts and actions, which are less plentiful than pure videos and don't necessarily correspond to meaningful tasks [4], but capture valuable correlations between a robot's actions and changes in the environment and are easy to collect on a given robot; (3) Small sets of high-quality sensorimotor demonstrations for a target task in a target environment. Thus, a scalable model architecture for robotic manipulation must be able to learn primarily from videos, while being extra data-efficient on sensorimotor training sequences and the small amount target demonstrations. PLEX, the PLanning-EXecution architecture we propose, is designed to take advantage of data sources of these types.
Learning Performance-Improving Code Edits
Shypula, Alexander, Madaan, Aman, Zeng, Yimeng, Alon, Uri, Gardner, Jacob, Hashemi, Milad, Neubig, Graham, Ranganathan, Parthasarathy, Bastani, Osbert, Yazdanbakhsh, Amir
With the waning of Moore's law, optimizing program performance has become a major focus of software research. However, high-level optimizations such as API and algorithm changes remain elusive due to the difficulty of understanding the semantics of code. Simultaneously, pretrained large language models (LLMs) have demonstrated strong capabilities at solving a wide range of programming tasks. To that end, we introduce a framework for adapting LLMs to high-level program optimization. First, we curate a dataset of performance-improving edits made by human programmers of over 77K competitive C++ programming submission pairs, accompanied by extensive unit tests. A major challenge is the significant variability of measuring performance on commodity hardware, which can lead to spurious "improvements". To isolate and reliably evaluate the impact of program optimizations, we design an environment based on the gem5 full system simulator, the de facto simulator used in academia and industry. Next, we propose a broad range of adaptation strategies for code optimization; for prompting, these include retrieval-based few-shot prompting and chain-of-thought, and for finetuning, these include performance-conditioned generation and synthetic data augmentation based on self-play. A combination of these techniques achieves an average speedup of 5.65X on CodeLlama-13B and 6.86X on GPT-3.5, surpassing the best human performance (4.06X). We find our proposed performance-conditioned generation is particularly effective at improving performance as well as increasing the fraction of optimized programs.
MarioGPT: Open-Ended Text2Level Generation through Large Language Models
Sudhakaran, Shyam, González-Duque, Miguel, Glanois, Claire, Freiberger, Matthias, Najarro, Elias, Risi, Sebastian
Procedural Content Generation (PCG) is a technique to generate complex and diverse environments in an automated way. However, while generating content with PCG methods is often straightforward, generating meaningful content that reflects specific intentions and constraints remains challenging. Furthermore, many PCG algorithms lack the ability to generate content in an open-ended manner. Recently, Large Language Models (LLMs) have shown to be incredibly effective in many diverse domains. These trained LLMs can be fine-tuned, re-using information and accelerating training for new tasks. Here, we introduce MarioGPT, a fine-tuned GPT2 model trained to generate tile-based game levels, in our case Super Mario Bros levels. MarioGPT can not only generate diverse levels, but can be text-prompted for controllable level generation, addressing one of the key challenges of current PCG techniques. As far as we know, MarioGPT is the first text-to-level model and combined with novelty search it enables the generation of diverse levels with varying play-style dynamics (i.e.
Designing Robust Transformers using Robust Kernel Density Estimation
Han, Xing, Ren, Tongzheng, Nguyen, Tan Minh, Nguyen, Khai, Ghosh, Joydeep, Ho, Nhat
Transformer-based architectures have recently exhibited remarkable successes across different domains beyond just powering large language models. However, existing approaches typically focus on predictive accuracy and computational cost, largely ignoring certain other practical issues such as robustness to contaminated samples. In this paper, by re-interpreting the self-attention mechanism as a non-parametric kernel density estimator, we adapt classical robust kernel density estimation methods to develop novel classes of transformers that are resistant to adversarial attacks and data contamination. We first propose methods that down-weight outliers in RKHS when computing the self-attention operations. We empirically show that these methods produce improved performance over existing state-of-the-art methods, particularly on image data under adversarial attacks. Then we leverage the median-of-means principle to obtain another efficient approach that results in noticeably enhanced performance and robustness on language modeling and time series classification tasks. Our methods can be combined with existing transformers to augment their robust properties, thus promising to impact a wide variety of applications.
Leveraging Large (Visual) Language Models for Robot 3D Scene Understanding
Chen, William, Hu, Siyi, Talak, Rajat, Carlone, Luca
Abstract semantic 3D scene understanding is a problem of critical importance in robotics. As robots still lack the common-sense knowledge about household objects and locations of an average human, we investigate the use of pre-trained language models to impart common sense for scene understanding. We introduce and compare a wide range of scene classification paradigms that leverage language only (zero-shot, embedding-based, and structured-language) or vision and language (zero-shot and fine-tuned). We find that the best approaches in both categories yield $\sim 70\%$ room classification accuracy, exceeding the performance of pure-vision and graph classifiers. We also find such methods demonstrate notable generalization and transfer capabilities stemming from their use of language.
5 Key Updates in GPT-4 Turbo, OpenAI's Newest Model
OpenAI recently announced multiple new features for ChatGPT and other artificial intelligence tools during its recent developer conference. The upcoming launch of a creator tool for chatbots, called GPTs (short for generative pretrained transformers), and a new model for ChatGPT, called GPT-4 Turbo, are two of the most important announcements from the company's event. This isn't the first time OpenAI has given ChatGPT a new model. Earlier this year, OpenAI updated the algorithm for ChatGPT from GPT-3.5 to GPT-4. Are you curious how the GPT-4 Turbo version of the chatbot will be different when it rolls out later this year?
ChatGPT Made OpenAI a Powerhouse. Here's What Could Undo It.
This article is from Big Technology, a newsletter by Alex Kantrowitz. It's been a year of glossy profiles, breathless accolades, and billions in new funding for OpenAI, but the ChatGPT maker is far more vulnerable than the popular narrative suggests. Amid a seemingly unstoppable ascent, the company is facing fierce competition, a rising open-source movement, and pressure to deliver hits in an unpredictable discipline. While its marquee product has become practically synonymous with A.I., its perch atop the field is less than rock solid. OpenAI's weakness stems in part from its strength. It popularized generative A.I. by taking others' innovations--like the transformer model--and building stellar products on top of them.
PB-LLM: Partially Binarized Large Language Models
Shang, Yuzhang, Yuan, Zhihang, Wu, Qiang, Dong, Zhen
This paper explores network binarization, a radical form of quantization, compressing model weights to a single bit, specifically for Large Language Models (LLMs) compression. Due to previous binarization methods collapsing LLMs, we propose a novel approach, Partially-Binarized LLM (PB-LLM), which can achieve extreme low-bit quantization while maintaining the linguistic reasoning capacity of quantized LLMs. Specifically, our exploration first uncovers the ineffectiveness of naive applications of existing binarization algorithms and highlights the imperative role of salient weights in achieving low-bit quantization. Thus, PB-LLM filters a small ratio of salient weights during binarization, allocating them to higher-bit storage, i.e., partially-binarization. PB-LLM is extended to recover the capacities of quantized LMMs, by analyzing from the perspective of post-training quantization (PTQ) and quantization-aware training (QAT). Under PTQ, combining the concepts from GPTQ, we reconstruct the binarized weight matrix guided by the Hessian matrix and successfully recover the reasoning capacity of PB-LLM in low-bit. Under QAT, we freeze the salient weights during training, explore the derivation of optimal scaling factors crucial for minimizing the quantization error, and propose a scaling mechanism based on this derived scaling strategy for residual binarized weights. Those explorations and the developed methodologies significantly contribute to rejuvenating the performance of low-bit quantized LLMs and present substantial advancements in the field of network binarization for LLMs.The code is available at https://github.com/hahnyuan/BinaryLLM.
Certified Deductive Reasoning with Language Models
Poesia, Gabriel, Gandhi, Kanishk, Zelikman, Eric, Goodman, Noah D.
Language models often achieve higher accuracy when reasoning step-by-step in complex tasks. However, even when arriving at a correct final answer, their rationales are often logically unsound or inconsistent. This is a major issue when reliable reasoning traces are needed, such when fine-tuning on model-generated reasoning for self-improvement. To tackle these issues, we introduce a class of tools for language models called \emph{guides}, that use state and incremental constraints to guide generation. A guide can be invoked by the model to constrain its own generation to a set of valid statements given by the tool. In turn, the model's choices can change the guide's state. We show how a general system for logical reasoning can be used as a guide, which we call \textsc{LogicGuide}. Given a reasoning problem in natural language, a model can formalize its assumptions for \textsc{LogicGuide} and guarantee that its step-by-step reasoning is sound. In experiments on PrOntoQA, ProofWriter and Syllogism Validity datasets, \textsc{LogicGuide} significantly improves the performance of GPT-3, GPT-3.5 Turbo and LLaMA (accuracy gains up to 35\%), while drastically reducing \emph{content effects} -- the interference between unwanted prior assumptions and reasoning, which humans and language models suffer from. We then explore bootstrapping GPT-3.5 Turbo and LLaMA using their own reasoning traces. We find that LogicGuide is critical: by training only on certified self-generated reasoning, models can self-improve, avoiding learning from their own hallucinations. Moreover, bootstrapped models enjoy significant boosts on ReClor, a challenging real-world reasoning dataset, even when not relying on formalization at inference time.
Teaching Language Models to Hallucinate Less with Synthetic Tasks
Jones, Erik, Palangi, Hamid, Simões, Clarisse, Chandrasekaran, Varun, Mukherjee, Subhabrata, Mitra, Arindam, Awadallah, Ahmed, Kamar, Ece
Large language models (LLMs) frequently hallucinate on abstractive summarization tasks such as document-based question-answering, meeting summarization, and clinical report generation, even though all necessary information is included in context. However, optimizing LLMs to hallucinate less on these tasks is challenging, as hallucination is hard to efficiently evaluate at each optimization step. In this work, we show that reducing hallucination on a synthetic task can also reduce hallucination on real-world downstream tasks. Our method, SynTra, first designs a synthetic task where hallucinations are easy to elicit and measure. It next optimizes the LLM's system message via prefix-tuning on the synthetic task, and finally transfers the system message to realistic, hard-to-optimize tasks. Across three realistic abstractive summarization tasks, SynTra reduces hallucination for two 13B-parameter LLMs using only a synthetic retrieval task for supervision. We also find that optimizing the system message rather than the model weights can be critical; fine-tuning the entire model on the synthetic task can counterintuitively increase hallucination. Overall, SynTra demonstrates that the extra flexibility of working with synthetic data can help mitigate undesired behaviors in practice.