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Deconfounded Causal Collaborative Filtering

arXiv.org Artificial Intelligence

Recommender systems may be confounded by various types of confounding factors (also called confounders) that may lead to inaccurate recommendations and sacrificed recommendation performance. Current approaches to solving the problem usually design each specific model for each specific confounder. However, real-world systems may include a huge number of confounders and thus designing each specific model for each specific confounder could be unrealistic. More importantly, except for those ``explicit confounders'' that experts can manually identify and process such as item's position in the ranking list, there are also many ``latent confounders'' that are beyond the imagination of experts. For example, users' rating on a song may depend on their current mood or the current weather, and users' preference on ice creams may depend on the air temperature. Such latent confounders may be unobservable in the recorded training data. To solve the problem, we propose Deconfounded Causal Collaborative Filtering (DCCF). We first frame user behaviors with unobserved confounders into a causal graph, and then we design a front-door adjustment model carefully fused with machine learning to deconfound the influence of unobserved confounders. Experiments on real-world datasets show that our method is able to deconfound unobserved confounders to achieve better recommendation performance.


Family killed in Russian shelling in Ukraine's Kherson

Al Jazeera

Russian shelling has killed seven people, including a 23-day-old infant, and wounded 20 others in Ukraine's southern region of Kherson, prompting local officials to declare a day of mourning. Kyiv reclaimed part of Kherson from Russian occupation last November, but Kremlin troops have continued shelling the regional capital and areas around it from across the Dnipro River. A couple, their 23-day-old child and another man were killed in the village of Shyroka Balka, Interior Minister Ihor Klymenko said on Sunday. The couple's 12-year-old son was critically wounded and died in hospital. "The terrorists will never willingly stop killing civilians," Klymenko wrote in a Telegram post.


Agent-Controller Representations: Principled Offline RL with Rich Exogenous Information

arXiv.org Artificial Intelligence

Learning to control an agent from data collected offline in a rich pixel-based visual observation space is vital for real-world applications of reinforcement learning (RL). A major challenge in this setting is the presence of input information that is hard to model and irrelevant to controlling the agent. This problem has been approached by the theoretical RL community through the lens of exogenous information, i.e, any control-irrelevant information contained in observations. For example, a robot navigating in busy streets needs to ignore irrelevant information, such as other people walking in the background, textures of objects, or birds in the sky. In this paper, we focus on the setting with visually detailed exogenous information, and introduce new offline RL benchmarks offering the ability to study this problem. We find that contemporary representation learning techniques can fail on datasets where the noise is a complex and time dependent process, which is prevalent in practical applications. To address these, we propose to use multi-step inverse models, which have seen a great deal of interest in the RL theory community, to learn Agent-Controller Representations for Offline-RL (ACRO). Despite being simple and requiring no reward, we show theoretically and empirically that the representation created by this objective greatly outperforms baselines.


Faithful to Whom? Questioning Interpretability Measures in NLP

arXiv.org Artificial Intelligence

A common approach to quantifying model interpretability is to calculate faithfulness metrics based on iteratively masking input tokens and measuring how much the predicted label changes as a result. However, we show that such metrics are generally not suitable for comparing the interpretability of different neural text classifiers as the response to masked inputs is highly model-specific. We demonstrate that iterative masking can produce large variation in faithfulness scores between comparable models, and show that masked samples are frequently outside the distribution seen during training. We further investigate the impact of adversarial attacks and adversarial training on faithfulness scores, and demonstrate the relevance of faithfulness measures for analyzing feature salience in text adversarial attacks. Our findings provide new insights into the limitations of current faithfulness metrics and key considerations to utilize them appropriately.


Video Captioning with Aggregated Features Based on Dual Graphs and Gated Fusion

arXiv.org Artificial Intelligence

The application of video captioning models aims at translating the content of videos by using accurate natural language. Due to the complex nature inbetween object interaction in the video, the comprehensive understanding of spatio-temporal relations of objects remains a challenging task. Existing methods often fail in generating sufficient feature representations of video content. In this paper, we propose a video captioning model based on dual graphs and gated fusion: we adapt two types of graphs to generate feature representations of video content and utilize gated fusion to further understand these different levels of information. Using a dual-graphs model to generate appearance features and motion features respectively can utilize the content correlation in frames to generate various features from multiple perspectives. Among them, dual-graphs reasoning can enhance the content correlation in frame sequences to generate advanced semantic features; The gated fusion, on the other hand, aggregates the information in multiple feature representations for comprehensive video content understanding. The experiments conducted on worldly used datasets MSVD and MSR-VTT demonstrate state-of-the-art performance of our proposed approach.


Slice Transformer and Self-supervised Learning for 6DoF Localization in 3D Point Cloud Maps

arXiv.org Artificial Intelligence

Precise localization is critical for autonomous vehicles. We present a self-supervised learning method that employs Transformers for the first time for the task of outdoor localization using LiDAR data. We propose a pre-text task that reorganizes the slices of a $360^\circ$ LiDAR scan to leverage its axial properties. Our model, called Slice Transformer, employs multi-head attention while systematically processing the slices. To the best of our knowledge, this is the first instance of leveraging multi-head attention for outdoor point clouds. We additionally introduce the Perth-WA dataset, which provides a large-scale LiDAR map of Perth city in Western Australia, covering $\sim$4km$^2$ area. Localization annotations are provided for Perth-WA. The proposed localization method is thoroughly evaluated on Perth-WA and Appollo-SouthBay datasets. We also establish the efficacy of our self-supervised learning approach for the common downstream task of object classification using ModelNet40 and ScanNN datasets. The code and Perth-WA data will be publicly released.


PInKS: Preconditioned Commonsense Inference with Minimal Supervision

arXiv.org Artificial Intelligence

Reasoning with preconditions such as "glass can be used for drinking water unless the glass is shattered" remains an open problem for language models. The main challenge lies in the scarcity of preconditions data and the model's lack of support for such reasoning. We present PInKS, Preconditioned Commonsense Inference with WeaK Supervision, an improved model for reasoning with preconditions through minimum supervision. We show, both empirically and theoretically, that PInKS improves the results on benchmarks focused on reasoning with the preconditions of commonsense knowledge (up to 40% Macro-F1 scores). We further investigate PInKS through PAC-Bayesian informativeness analysis, precision measures, and ablation study.


PaCo: Preconditions Attributed to Commonsense Knowledge

arXiv.org Artificial Intelligence

Humans can seamlessly reason with circumstantial preconditions of commonsense knowledge. We understand that a glass is used for drinking water, unless the glass is broken or the water is toxic. Despite state-of-the-art (SOTA) language models' (LMs) impressive performance on inferring commonsense knowledge, it is unclear whether they understand the circumstantial preconditions. To address this gap, we propose a novel challenge of reasoning with circumstantial preconditions. We collect a dataset, called PaCo, consisting of 12.4 thousand preconditions of commonsense statements expressed in natural language. Based on this dataset, we create three canonical evaluation tasks and use them to examine the capability of existing LMs to understand situational preconditions. Our results reveal a 10-30% gap between machine and human performance on our tasks, which shows that reasoning with preconditions is an open challenge.


I just reread George Orwell's '1984' and the novel is scarier than ever

FOX News

'The Big Weekend Show' panelists discuss Elon Musk offering to pay users' legal bills if they are'unfairly treated' by employers for likes or posts on X, the platform formerly known as Twitter. That's what George Orwell would say if he could visit our world, 75 years after he wrote his final novel, "1984." Orwell sought to demonstrate the dangers not just of totalitarianism but of a world where words lose their meaning. Many of the terms he coined for the novel have since entered common discourse -- "thought police," "Big Brother," "doublethink," and the "memory hole," to name a few. And of course the adjective "Orwellian" comes to us because of this book.


'There's no such thing as a neutral algorithm': the existential AI exhibition confronting Sydney

The Guardian

When Y2K seemed like the world's most pressing technological concern, the Mexican-Canadian artist Rafael Lozano-Hemmer was using a dictionary and a set of grammatical rules to teach a computer how to write questions. The program he built can make enquiries in Spanish, English, German and French, in 4.7tn possible combinations. When the artwork showed at the San Francisco Museum of Modern Art last year, it still had 271,000 years of new questions to ask. Which is to say, Lozano-Hemmer has been working with generative technology long enough to have learned a powerful lesson: "There is no such thing as a neutral algorithm." This lesson was reiterated to the Bafta-winning media artist in a spectacular, humiliating fashion at Miami Art Basel a little over a decade ago.