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Negative-Prompt-driven Alignment for Generative Language Model

arXiv.org Artificial Intelligence

Their vast parameters (Kaplan et al., 2020) and extensive training data grant them strong capabilities, but they may still generate outputs that conflict with human values, such as helpless or harmful content. Therefore, AI alignment research has emerged with the goal of fine-tuning LLMs to make them align with human values. One of the most popular alignment methods is RLHF(Reinforcement Learning from Human Feedback) framework (Stiennon et al., 2020; Ziegler et al., 2019; Ouyang et al., 2022), which initially apply supervised fine-tuning to the base model to follow human instructions. Subsequently, a reward model is trained from the human preference data, then optimizing the LLM via PPO algorithm (Schulman et al., 2017) to align with huamn preferences. RLHF requires at least three large models for training, making the process quite complex, and the PPO algorithm itself is highly sophisticated and challenging to parameter-tuning. This drives researchers to explore simpler and more straightforward methods to align language models with human preferences. To simplify alignment, (Rafailov et al., 2023) introduced Direct Preference Optimization (DPO), which provides a closed-form alignment solution and directly uses human preferences for alignment without a separate reward model. Other approaches, like RRHF (Yuan et al., 2023a) and PRO (Song et al., 2024), use SFT-like loss based on multi-ranking datasets to provide richer supervision for alignment.


HumVI: A Multilingual Dataset for Detecting Violent Incidents Impacting Humanitarian Aid

arXiv.org Artificial Intelligence

Humanitarian organizations can enhance their effectiveness by analyzing data to discover trends, gather aggregated insights, manage their security risks, support decision-making, and inform advocacy and funding proposals. However, data about violent incidents with direct impact and relevance for humanitarian aid operations is not readily available. An automatic data collection and NLP-backed classification framework aligned with humanitarian perspectives can help bridge this gap. In this paper, we present HumVI - a dataset comprising news articles in three languages (English, French, Arabic) containing instances of different types of violent incidents categorized by the humanitarian sector they impact, e.g., aid security, education, food security, health, and protection. Reliable labels were obtained for the dataset by partnering with a data-backed humanitarian organization, Insecurity Insight. We provide multiple benchmarks for the dataset, employing various deep learning architectures and techniques, including data augmentation and mask loss, to address different task-related challenges, e.g., domain expansion. The dataset is publicly available at https://github.com/dataminr-ai/humvi-dataset.


LoRTA: Low Rank Tensor Adaptation of Large Language Models

arXiv.org Artificial Intelligence

Low Rank Adaptation (LoRA) is a popular Parameter Efficient Fine Tuning (PEFT) method that effectively adapts large pre-trained models for downstream tasks. LoRA parameterizes model updates using low-rank matrices at each layer, significantly reducing the number of trainable parameters and, consequently, resource requirements during fine-tuning. However, the lower bound on the number of trainable parameters remains high due to the use of the low-rank matrix model. In this paper, we address this limitation by proposing a novel approach that employs a low rank tensor parametrization for model updates. The proposed low rank tensor model can significantly reduce the number of trainable parameters, while also allowing for finer-grained control over adapter size. Our experiments on Natural Language Understanding, Instruction Tuning, Preference Optimization and Protein Folding benchmarks demonstrate that our method is both efficient and effective for fine-tuning large language models, achieving a substantial reduction in the number of parameters while maintaining comparable performance.


Data-adaptive Differentially Private Prompt Synthesis for In-Context Learning

arXiv.org Machine Learning

Large Language Models (LLMs) rely on the contextual information embedded in examples/demonstrations to perform in-context learning (ICL). To mitigate the risk of LLMs potentially leaking private information contained in examples in the prompt, we introduce a novel data-adaptive differentially private algorithm called AdaDPSyn to generate synthetic examples from the private dataset and then use these synthetic examples to perform ICL. The objective of AdaDPSyn is to adaptively adjust the noise level in the data synthesis mechanism according to the inherent statistical properties of the data, thereby preserving high ICL accuracy while maintaining formal differential privacy guarantees. A key innovation in AdaDPSyn is the Precision-Focused Iterative Radius Reduction technique, which dynamically refines the aggregation radius - the scope of data grouping for noise addition - based on patterns observed in data clustering, thereby minimizing the amount of additive noise. We conduct extensive experiments on standard benchmarks and compare AdaDPSyn with DP few-shot generation algorithm (Tang et al., 2023). The experiments demonstrate that AdaDPSyn not only outperforms DP few-shot generation, but also maintains high accuracy levels close to those of non-private baselines, providing an effective solution for ICL with privacy protection.


Mitigating Suboptimality of Deterministic Policy Gradients in Complex Q-functions

arXiv.org Machine Learning

In reinforcement learning, off-policy actor-critic approaches like DDPG and TD3 are based on the deterministic policy gradient. Herein, the Q-function is trained from off-policy environment data and the actor (policy) is trained to maximize the Q-function via gradient ascent. We observe that in complex tasks like dexterous manipulation and restricted locomotion, the Q-value is a complex function of action, having several local optima or discontinuities. This poses a challenge for gradient ascent to traverse and makes the actor prone to get stuck at local optima. To address this, we introduce a new actor architecture that combines two simple insights: (i) use multiple actors and evaluate the Q-value maximizing action, and (ii) learn surrogates to the Q-function that are simpler to optimize with gradient-based methods. We evaluate tasks such as restricted locomotion, dexterous manipulation, and large discrete-action space recommender systems and show that our actor finds optimal actions more frequently and outperforms alternate actor architectures.


Efficient, Accurate and Stable Gradients for Neural ODEs

arXiv.org Machine Learning

Neural ODEs are a recently developed model class that combine the strong model priors of differential equations with the high-capacity function approximation of neural networks. One advantage of Neural ODEs is the potential for memory-efficient training via the continuous adjoint method. However, memory-efficient training comes at the cost of approximate gradients. Therefore, in practice, gradients are often obtained by simply backpropagating through the internal operations of the forward ODE solve - incurring high memory cost. Interestingly, it is possible to construct algebraically reversible ODE solvers that allow for both exact gradients and the memory-efficiency of the continuous adjoint method. Unfortunately, current reversible solvers are low-order and suffer from poor numerical stability. The use of these methods in practice is therefore limited. In this work, we present a class of algebraically reversible solvers that are both high-order and numerically stable. Moreover, any explicit numerical scheme can be made reversible by our method. This construction naturally extends to numerical schemes for Neural CDEs and SDEs.


Shallow diffusion networks provably learn hidden low-dimensional structure

arXiv.org Machine Learning

Generative models learn to sample from a target probability distribution given a dataset of examples. Applications are pervasive, and include language modeling (Li et al., 2022), high-fidelity image generation (Rombach et al., 2022), de-novo drug design (Watson et al., 2023), and molecular dynamics (Arts et al., 2023). Recent years have witnessed extremely rapid advancements in the field of generative modeling, particularly with the development of models based on dynamical transport of measure(Santambrogio, 2015), such as diffusion-based generative models (Ho et al., 2020; Song et al., 2021), stochastic interpolants (Albergo et al., 2023), flow matching(Lipman et al., 2023), and rectified flow(Liu et al., 2023) approaches. Yet, despite their strong empirical performance and well-grounded mathematical formulation, a theoretical understanding of how and why these large-scale generative models work is still in its infancy. A promising line of recent research has shown that the problem of sampling from an arbitrarily complex distribution can be reduced to unsupervised learning: for diffusion models, if an accurate velocity or score field can be estimated from data, then high-quality samples can be generated via numerical simulation(Chen et al., 2023a; Lee et al., 2023). While deeply insightful, these works leave open the difficulty of statistical estimation, and therefore raise the possibility that the sampling problem's true difficulty is hidden in the complexity of learning. In this work, we address this fundamental challenge by presenting an end-to-end analysis of sampling with score-based diffusion models. To balance tractability of the analysis with empirical relevance, we study the Barron space of single-layer neural networks (E et al., 2019; Bach, 2017).


'I, Robot' director claims Elon Musk is STEALING his ideas - as he posts incredibly similar photos of his sci-fi creations and Tesla's

Daily Mail - Science & tech

Elon Musk officially unveiled more futuristic Tesla devices last week, but it seems not everyone is thrilled. Australian-Egyptian filmmaker Alex Proyas has accused the billionaire tech boss of poaching his ideas from his 2004 film'I, Robot'. On X (Twitter), Proyas posted photos of futuristic tech from'I, Robot' next to three remarkably-similar Tesla products – Optimus, Robovan and Robotaxi. Proyas also included the message: 'Hey Elon, Can I have my designs back please?' Robovan and Robotaxi were unveiled on Thursday at a Tesla event dubbed'We Robot' – a blatant reference to the film. Alex Proyas posted photos from his 2004 film'I, Robot' (left) next to Tesla's remarkably similar designs (right) Tesla's Optimus has a striking resemblance to Sonny, the fictional robot protagonist from the movie, starring Will Smith (pictured) Set in Chicago in 2035, 'I, Robot' depicts intelligent robots filling public service positions in a dystopian world.


Pokémon maker confirms it was victim of hack

BBC News

Pokémon maker confirms it was victim of hack The Pokémon CompanyPokémon is one of the world's best-known entertainment brands Pokémon maker Game Freak has confirmed it was the victim of a data leak after information appeared online over the weekend. The company, which has developed the Nintendo-exclusive video game series since 1996, said its servers were hacked in August this year. A statement said 2,606 items containing the names and email addresses of current, former and contract employees were accessed. The company did not comment on other information shared online claiming to show details of unreleased and upcoming projects. Game Freak said it would individually contact those affected where possible, and strengthen security measures to prevent similar hacks in future.


HumanFT: A Human-like Fingertip Multimodal Visuo-Tactile Sensor

arXiv.org Artificial Intelligence

Tactile sensors play a crucial role in enabling robots to interact effectively and safely with objects in everyday tasks. In particular, visuotactile sensors have seen increasing usage in two and three-fingered grippers due to their high-quality feedback. However, a significant gap remains in the development of sensors suitable for humanoid robots, especially five-fingered dexterous hands. One reason is because of the challenges in designing and manufacturing sensors that are compact in size. In this paper, we propose HumanFT, a multimodal visuotactile sensor that replicates the shape and functionality of a human fingertip. To bridge the gap between human and robotic tactile sensing, our sensor features real-time force measurements, high-frequency vibration detection, and overtemperature alerts. To achieve this, we developed a suite of fabrication techniques for a new type of elastomer optimized for force propagation and temperature sensing. Besides, our sensor integrates circuits capable of sensing pressure and vibration. These capabilities have been validated through experiments. The proposed design is simple and cost-effective to fabricate. We believe HumanFT can enhance humanoid robots' perception by capturing and interpreting multimodal tactile information.