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Hierarchical Topology Isomorphism Expertise Embedded Graph Contrastive Learning

arXiv.org Artificial Intelligence

Graph contrastive learning (GCL) aims to align the positive features while differentiating the negative features in the latent space by minimizing a pair-wise contrastive loss. As the embodiment of an outstanding discriminative unsupervised graph representation learning approach, GCL achieves impressive successes in various graph benchmarks. However, such an approach falls short of recognizing the topology isomorphism of graphs, resulting in that graphs with relatively homogeneous node features cannot be sufficiently discriminated. By revisiting classic graph topology recognition works, we disclose that the corresponding expertise intuitively complements GCL methods. To this end, we propose a novel hierarchical topology isomorphism expertise embedded graph contrastive learning, which introduces knowledge distillations to empower GCL models to learn the hierarchical topology isomorphism expertise, including the graph-tier and subgraph-tier. On top of this, the proposed method holds the feature of plug-and-play, and we empirically demonstrate that the proposed method is universal to multiple state-of-the-art GCL models. The solid theoretical analyses are further provided to prove that compared with conventional GCL methods, our method acquires the tighter upper bound of Bayes classification error. We conduct extensive experiments on real-world benchmarks to exhibit the performance superiority of our method over candidate GCL methods, e.g., for the real-world graph representation learning experiments, the proposed method beats the state-of-the-art method by 0.23% on unsupervised representation learning setting, 0.43% on transfer learning setting. Our code is available at https://github.com/jyf123/HTML.


Improving Generalization of Alignment with Human Preferences through Group Invariant Learning

arXiv.org Artificial Intelligence

The success of AI assistants based on language models (LLMs) hinges crucially on Reinforcement Learning from Human Feedback (RLHF), which enables the generation of responses more aligned with human preferences. As universal AI assistants, there's a growing expectation for them to perform consistently across various domains. However, previous work shows that Reinforcement Learning (RL) often exploits shortcuts to attain high rewards and overlooks challenging samples. This focus on quick reward gains undermines both the stability in training and the model's ability to generalize to new, unseen data. In this work, we propose a novel approach that can learn a consistent policy via RL across various data groups or domains. Given the challenges associated with acquiring group annotations, our method automatically classifies data into different groups, deliberately maximizing performance variance. Then, we optimize the policy to perform well on challenging groups. Lastly, leveraging the established groups, our approach adaptively adjusts the exploration space, allocating more learning capacity to more challenging data and preventing the model from over-optimizing on simpler data. Experimental results indicate that our approach significantly enhances training stability and model generalization.


MENLI: Robust Evaluation Metrics from Natural Language Inference

arXiv.org Artificial Intelligence

Recently proposed BERT-based evaluation metrics for text generation perform well on standard benchmarks but are vulnerable to adversarial attacks, e.g., relating to information correctness. We argue that this stems (in part) from the fact that they are models of semantic similarity. In contrast, we develop evaluation metrics based on Natural Language Inference (NLI), which we deem a more appropriate modeling. We design a preference-based adversarial attack framework and show that our NLI based metrics are much more robust to the attacks than the recent BERT-based metrics. On standard benchmarks, our NLI based metrics outperform existing summarization metrics, but perform below SOTA MT metrics. However, when combining existing metrics with our NLI metrics, we obtain both higher adversarial robustness (15%-30%) and higher quality metrics as measured on standard benchmarks (+5% to 30%).


Japan-owned tanker attacked by drone fired from Iran in Indian Ocean

The Japan Times

A Japanese-owned commercial tanker was attacked by a drone launched from Iran in the Indian Ocean on Saturday, causing a fire but leaving no one injured, the U.S. Department of Defense said. The Liberian-flagged, Netherlands-operated chemical tanker was struck about 370 kilometers off India "by a one-way attack drone fired from Iran," the Pentagon said in a statement, adding the fire on board has been extinguished. The Associated Press reported the tanker had ties with Israel, citing a British maritime security firm. The tanker, which was carrying 20 Indians and one Vietnamese, had left Saudi Arabia on Tuesday and was heading to Mangalore, southwestern India, according to the U.S. Defense Department and the Indian Coast Guard. But the vessel decided to head to Mumbai for repairs and to have the damage assessed with the assistance of the Indian Coast Guard.


The real Santa's face: ID software sorts Father Christmas from his stand-ins

The Guardian

Scientists have created a Santa-detection machine and used it to prove what children have been telling adults for generations – that Santa has a unique face which clearly distinguishes him from other elderly bearded men. Previous research has suggested that children as young as three can identify Santa Claus based on his distinctive appearance. "Santa Claus or Father Christmas is obviously a very recognisable person, but we wondered whether this is because of his clothing, his beard or his face?" said Dr Thomas Wright, a clinical geneticist at the University of Manchester, who led the research. "Until now no one has ever systematically and scientifically interrogated the modern face of Father Christmas." To investigate, Wright and his colleagues trained a deep-learning facial-recognition algorithm – similar to the facial ID software used to unlock smartphones or identify people in digital photo libraries – on multiple images of Santa gathered from the internet.


Iran appears to have struck ship off Indian coast with UAV: US Official

FOX News

Former CENTCOM Spokesperson and retired U.S. Army Colonel Joe Buccino discusses Iran's involvement in Houthi attacks and the U.S.' approach to deterrence and response. Iran appears to have struck a ship off the Indian coast with an unmanned aerial vehicle, a U.S. official told Fox News on Saturday. It comes as Houthi militants targeted multiple cargo ships on Saturday, as the group fired two anti-ship ballistic missiles into international shipping lanes located in the Southern Red Sea, according to U.S. Central Command. No ships were impacted by the ballistic missiles, officials said. The USS Laboon shot down four unmanned aerial drones on Saturday which originated from areas that the Houthis control in Yemen.


Nowcasting Madagascar's real GDP using machine learning algorithms

arXiv.org Artificial Intelligence

We investigate the predictive power of different machine learning algorithms to nowcast Madagascar's gross domestic product (GDP). We trained popular regression models, including linear regularized regression (Ridge, Lasso, Elastic-net), dimensionality reduction model (principal component regression), k-nearest neighbors algorithm (k-NN regression), support vector regression (linear SVR), and tree-based ensemble models (Random forest and XGBoost regressions), on 10 Malagasy quarterly macroeconomic leading indicators over the period 2007Q1--2022Q4, and we used simple econometric models as a benchmark. We measured the nowcast accuracy of each model by calculating the root mean square error (RMSE), mean absolute error (MAE), and mean absolute percentage error (MAPE). Our findings reveal that the Ensemble Model, formed by aggregating individual predictions, consistently outperforms traditional econometric models. We conclude that machine learning models can deliver more accurate and timely nowcasts of Malagasy economic performance and provide policymakers with additional guidance for data-driven decision making.


Multi-level biomedical NER through multi-granularity embeddings and enhanced labeling

arXiv.org Artificial Intelligence

Biomedical Named Entity Recognition (NER) is a fundamental task of Biomedical Natural Language Processing for extracting relevant information from biomedical texts, such as clinical records, scientific publications, and electronic health records. The conventional approaches for biomedical NER mainly use traditional machine learning techniques, such as Conditional Random Fields and Support Vector Machines or deep learning-based models like Recurrent Neural Networks and Convolutional Neural Networks. Recently, Transformer-based models, including BERT, have been used in the domain of biomedical NER and have demonstrated remarkable results. However, these models are often based on word-level embeddings, limiting their ability to capture character-level information, which is effective in biomedical NER due to the high variability and complexity of biomedical texts. To address these limitations, this paper proposes a hybrid approach that integrates the strengths of multiple models. In this paper, we proposed an approach that leverages fine-tuned BERT to provide contextualized word embeddings, a pre-trained multi-channel CNN for character-level information capture, and following by a BiLSTM + CRF for sequence labelling and modelling dependencies between the words in the text. In addition, also we propose an enhanced labelling method as part of pre-processing to enhance the identification of the entity's beginning word and thus improve the identification of multi-word entities, a common challenge in biomedical NER. By integrating these models and the pre-processing method, our proposed model effectively captures both contextual information and detailed character-level information. We evaluated our model on the benchmark i2b2/2010 dataset, achieving an F1-score of 90.11. These results illustrate the proficiency of our proposed model in performing biomedical Named Entity Recognition.


Towards Consistent Language Models Using Declarative Constraints

arXiv.org Artificial Intelligence

Large language models have shown unprecedented abilities in generating linguistically coherent and syntactically correct natural language output. However, they often return incorrect and inconsistent answers to input questions. Due to the complexity and uninterpretability of the internally learned representations, it is challenging to modify language models such that they provide correct and consistent results. The data management community has developed various methods and tools for providing consistent answers over inconsistent datasets. In these methods, users specify the desired properties of data in a domain in the form of high-level declarative constraints. This approach has provided usable and scalable methods to delivering consistent information from inconsistent datasets. We aim to build upon this success and leverage these methods to modify language models such that they deliver consistent and accurate results. We investigate the challenges of using these ideas to obtain consistent and relevant answers from language models and report some preliminary empirical studies.


DeepArt: A Benchmark to Advance Fidelity Research in AI-Generated Content

arXiv.org Artificial Intelligence

This paper explores the image synthesis capabilities of GPT-4, a leading multi-modal large language model. We establish a benchmark for evaluating the fidelity of texture features in images generated by GPT-4, comprising manually painted pictures and their AI-generated counterparts. The contributions of this study are threefold: First, we provide an in-depth analysis of the fidelity of image synthesis features based on GPT-4, marking the first such study on this state-of-the-art model. Second, the quantitative and qualitative experiments fully reveals the limitations of the GPT-4 model in image synthesis. Third, we have compiled a unique benchmark of manual drawings and corresponding GPT-4-generated images, introducing a new task to advance fidelity research in AI-generated content (AIGC). The dataset is available at: \url{https://github.com/rickwang28574/DeepArt}.