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Removing Spurious Concepts from Neural Network Representations via Joint Subspace Estimation

arXiv.org Machine Learning

This crucially differs from existing methods, which only focus on the spurious concept features, risking the loss of vital main-task information. Furthermore, we make the identification of the subspaces systematic by introducing statistical tests that attribute directions in the embedding space to either the main-task or the spurious concept. The method, which we call Joint Subspace Estimation (JSE), is shown to be robust against the strength of the spurious correlation and to outperform existing concept-removal methods for a Toy dataset as well as benchmark datasets for image recognition (Waterbirds, CelebA) and natural language processing (MultiNLI). A high-level overview of the method is given in Figure 1. Figure 1: High-level overview of Joint Subspace Estimation (JSE) for concept removal: the input x is fed through a neural network f(x), from which we can extract the vector representation z. Within the vector representation, two orthogonal subspaces are identified: one related to the spurious concept (the background), and one to the main-task concept (bird type). JSE estimates the subspaces of the two concepts simultaneously to prevent mixing of spurious and main-task features.


Surrogate Active Subspaces for Jump-Discontinuous Functions

arXiv.org Machine Learning

Surrogate modeling and active subspaces have emerged as powerful paradigms in computational science and engineering. Porting such techniques to computational models in the social sciences brings into sharp relief their limitations in dealing with discontinuous simulators, such as Agent-Based Models, which have discrete outputs. Nevertheless, prior applied work has shown that surrogate estimates of active subspaces for such estimators can yield interesting results. But given that active subspaces are defined by way of gradients, it is not clear what quantity is being estimated when this methodology is applied to a discontinuous simulator. We begin this article by showing some pathologies that can arise when conducting such an analysis. This motivates an extension of active subspaces to discontinuous functions, clarifying what is actually being estimated in such analyses. We also conduct numerical experiments on synthetic test functions to compare Gaussian process estimates of active subspaces on continuous and discontinuous functions. Finally, we deploy our methodology on Flee, an agent-based model of refugee movement, yielding novel insights into which parameters of the simulation are most important across 8 displacement crises in Africa and the Middle East.


It Will Take More Than Robots to Manage the Robots

TIME - Tech

By now the sophistication of false information about Israel and Hamas is clear to anyone who opened their phone this week. As tech platforms rely ever more on artificial intelligence in their battle against disinformation, the havoc in the Middle East exposes the limits of technology to police technology's harms. It is more important than ever that we understand how global platforms like Meta, Google, and X, the platform formerly known as Twitter, make decisions about what content gets amplified and what taken down. It's not as though platforms didn't know they had a huge disinformation problem that human content moderators alone could not solve. Two years ago, Facebook whistleblower Frances Haugen detailed for Congress how growth and profit drove decisions: "The result has been more division, more harm, more lies, more threats and more combat," she testified.


Facebook whistleblower Frances Haugen issues chilling warning about AI and says it could soon have 'civilisation-altering impacts'

Daily Mail - Science & tech

Advances in artificial intelligence could have'civilisation-altering impacts' and rapidly increase the amount of dangerous misinformation being spread online, a former Facebook employee has warned. Whistleblower Frances Haugen said as AI became bigger and economies relied more on software running on data centres the world would start to see an'era of opacity' creep in. The former engineer and product manager - who quit Facebook in 2021 after leaking thousands of documents showing toxic content was being spread knowingly by the platform - said without stronger regulation there would be'a repeat of what we saw with social media' on a far greater scale. 'When we start getting into scalable systems that run on data centres, a very small number of people can have civilisation-impacting levels of power,' Ms Haugen told the National Press Club on Tuesday. 'At Facebook, there's a very small number of people who really understand how these algorithms work and yet it impacts what everyone sees in the news.


MacLaSa: Multi-Aspect Controllable Text Generation via Efficient Sampling from Compact Latent Space

arXiv.org Artificial Intelligence

Multi-aspect controllable text generation aims to generate fluent sentences that possess multiple desired attributes simultaneously. Traditional methods either combine many operators in the decoding stage, often with costly iteration or search in the discrete text space, or train separate controllers for each aspect, resulting in a degeneration of text quality due to the discrepancy between different aspects. To address these limitations, we introduce a novel approach for multi-aspect control, namely MacLaSa, that estimates compact latent space for multiple aspects and performs efficient sampling with a robust sampler based on ordinary differential equations (ODEs). To eliminate the domain gaps between different aspects, we utilize a Variational Autoencoder (VAE) network to map text sequences from varying data sources into close latent representations. The estimated latent space enables the formulation of joint energy-based models (EBMs) and the plugging in of arbitrary attribute discriminators to achieve multi-aspect control. Afterwards, we draw latent vector samples with an ODE-based sampler and feed sampled examples to the VAE decoder to produce target text sequences. Experimental results demonstrate that MacLaSa outperforms several strong baselines on attribute relevance and textual quality while maintaining a high inference speed.


AceGPT, Localizing Large Language Models in Arabic

arXiv.org Artificial Intelligence

This paper is devoted to the development of a localized Large Language Model (LLM) specifically for Arabic, a language imbued with unique cultural characteristics inadequately addressed by current mainstream models. Significant concerns emerge when addressing cultural sensitivity and local values. To address this, the paper proposes a comprehensive solution that includes further pre-training with Arabic texts, Supervised Fine-Tuning (SFT) utilizing native Arabic instructions, and GPT-4 responses in Arabic, alongside Reinforcement Learning with AI Feedback (RLAIF) employing a reward model attuned to local culture and values. The goal is to cultivate culturally cognizant and value-aligned Arabic LLMs capable of accommodating the diverse, application-specific needs of Arabic-speaking communities. Comprehensive evaluations reveal that the resulting model, dubbed 'AceGPT', sets the state-of-the-art standard for open Arabic LLMs across various benchmarks, including the instruction-following benchmark (i.e., Arabic Vicuna-80 and Arabic AlpacaEval), knowledge benchmark (i.e., Arabic MMLU and EXAMs), and the newly introduced Arabic Cultural and Value Alignment benchmark. Notably, AceGPT outperforms Turbo in the popular Vicuna-80 benchmark when evaluated with GPT-4, despite the benchmark's limited scale. Codes, data, and models are in https://github.com/FreedomIntelligence/AceGPT.


From Identifiable Causal Representations to Controllable Counterfactual Generation: A Survey on Causal Generative Modeling

arXiv.org Machine Learning

Deep generative models have shown tremendous success in data density estimation and data generation from finite samples. While these models have shown impressive performance by learning correlations among features in the data, some fundamental shortcomings are their lack of explainability, the tendency to induce spurious correlations, and poor out-of-distribution extrapolation. In an effort to remedy such challenges, one can incorporate the theory of causality in deep generative modeling. Structural causal models (SCMs) describe data-generating processes and model complex causal relationships and mechanisms among variables in a system. Thus, SCMs can naturally be combined with deep generative models. Causal models offer several beneficial properties to deep generative models, such as distribution shift robustness, fairness, and interoperability. We provide a technical survey on causal generative modeling categorized into causal representation learning and controllable counterfactual generation methods. We focus on fundamental theory, formulations, drawbacks, datasets, metrics, and applications of causal generative models in fairness, privacy, out-of-distribution generalization, and precision medicine. We also discuss open problems and fruitful research directions for future work in the field.


Robotic Perception of Transparent Objects: A Review

arXiv.org Artificial Intelligence

Transparent object perception is a rapidly developing research problem in artificial intelligence. The ability to perceive transparent objects enables robots to achieve higher levels of autonomy, unlocking new applications in various industries such as healthcare, services and manufacturing. Despite numerous datasets and perception methods being proposed in recent years, there is still a lack of in-depth understanding of these methods and the challenges in this field. To address this gap, this article provides a comprehensive survey of the platforms and recent advances for robotic perception of transparent objects. We highlight the main challenges and propose future directions of various transparent object perception tasks, i.e., segmentation, reconstruction, and pose estimation. We also discuss the limitations of existing datasets in diversity and complexity, and the benefits of employing multi-modal sensors, such as RGB-D cameras, thermal cameras, and polarised imaging, for transparent object perception. Furthermore, we identify perception challenges in complex and dynamic environments, as well as for objects with changeable geometries. Finally, we provide an interactive online platform to navigate each reference: \url{https://sites.google.com/view/transperception}.


Seeking Neural Nuggets: Knowledge Transfer in Large Language Models from a Parametric Perspective

arXiv.org Artificial Intelligence

Large Language Models (LLMs) inherently encode a wealth of knowledge within their parameters through pre-training on extensive corpora. While prior research has delved into operations on these parameters to manipulate the underlying implicit knowledge (encompassing detection, editing, and merging), there remains an ambiguous understanding regarding their transferability across models with varying scales. In this paper, we seek to empirically investigate knowledge transfer from larger to smaller models through a parametric perspective. To achieve this, we employ sensitivity-based techniques to extract and align knowledge-specific parameters between different LLMs. Moreover, the LoRA module is used as the intermediary mechanism for injecting the extracted knowledge into smaller models. Evaluations across four benchmarks validate the efficacy of our proposed method. Our findings highlight the critical factors contributing to the process of parametric knowledge transfer, underscoring the transferability of model parameters across LLMs of different scales. We release code and data at \url{https://github.com/maszhongming/ParaKnowTransfer}.


QADYNAMICS: Training Dynamics-Driven Synthetic QA Diagnostic for Zero-Shot Commonsense Question Answering

arXiv.org Artificial Intelligence

Zero-shot commonsense Question-Answering (QA) requires models to reason about general situations beyond specific benchmarks. State-of-the-art approaches fine-tune language models on QA pairs constructed from CommonSense Knowledge Bases (CSKBs) to equip the models with more commonsense knowledge in a QA context. However, current QA synthesis protocols may introduce noise from the CSKBs and generate ungrammatical questions and false negative options, which impede the model's ability to generalize. To address these issues, we propose QADYNAMICS, a training dynamics-driven framework for QA diagnostics and refinement. Our approach analyzes the training dynamics of each QA pair at both the question level and option level, discarding machine-detectable artifacts by removing uninformative QA pairs and mislabeled or false-negative options. Extensive experiments demonstrate the effectiveness of our approach, which outperforms all baselines while using only 33% of the synthetic data, even including LLMs such as ChatGPT. Moreover, expert evaluations confirm that our framework significantly improves the quality of QA synthesis. Our codes and model checkpoints are available at https://github.com/HKUST-KnowComp/QaDynamics.