South America
DLFormer: Enhancing Explainability in Multivariate Time Series Forecasting using Distributed Lag Embedding
Kim, Younghwi, Kim, Dohee, Sim, Sunghyun
Most of these data are multivariate, with multiple values at each time step (Wilms, Rombouts, & Croux, 2021; Lee, Kim & Sim, 2024). Consequently, utilizing multivariate time series data for knowledge extraction and application to societal issues is becoming increasingly prevalent, making multivariate time series prediction a challenging task widely regarded across most industries (Bidarkota, 1998). The traditional approach to addressing multivariate time series prediction problems involves using statistical methods, such as vector autoregression and autoregressive distributed lag (ARDL) models (Qu, Huang, She, Liad, & Lai, 2024). However, statistical methods may struggle to capture complex sequence patterns in the data because of irregularities and nonlinearities among the features (Salinas, Flunkert, Gasthaus, & Januschowski, 2020). Therefore, layer-based deep-learning models incorporating recurrent layers (Rumelhart, Hinton, & Williams, 1986), long short-term memory layers (Hochreiter & Schmidhuber, 1997), gated recurrent units (Chung, Gulcehre, Cho & Bengio, 2014), and attention mechanisms (Vaswani, Shazeer, Parmar, Uszkoreit, Jones, Gomez, & Polosukhin, 2017) have been widely explored in multivariate time series prediction (Catania, Grassi, & Ravazzolo, 2019). Deep learning-based models effectively learn sequential patterns in time series data and can outperform traditional statistical models, demonstrating superior prediction performance (Ortega, Otero, Solomon, Otero, & Fabregas, 2023). Another approach for improving the accuracy of multivariate time series prediction is to utilize models based on transformers, such as informers (Zhou, Zhang, Peng, Zhang, Li, Xiong, & Zhang, 2021) and autoformers (Wu, Xu, Wang, & Long, 2021). Transformer-based models effectively capture long-and short-term patterns in multivariate time series data and have surpassed traditional approaches in terms of prediction performance (Costa & Machado, 2023).
Do Recommender Systems Promote Local Music? A Reproducibility Study Using Music Streaming Data
Matrosova, Kristina, Marey, Lilian, Salha-Galvan, Guillaume, Louail, Thomas, Bodini, Olivier, Moussallam, Manuel
This paper examines the influence of recommender systems on local music representation, discussing prior findings from an empirical study on the LFM-2b public dataset. This prior study argued that different recommender systems exhibit algorithmic biases shifting music consumption either towards or against local content. However, LFM-2b users do not reflect the diverse audience of music streaming services. To assess the robustness of this study's conclusions, we conduct a comparative analysis using proprietary listening data from a global music streaming service, which we publicly release alongside this paper. We observe significant differences in local music consumption patterns between our dataset and LFM-2b, suggesting that caution should be exercised when drawing conclusions on local music based solely on LFM-2b. Moreover, we show that the algorithmic biases exhibited in the original work vary in our dataset, and that several unexplored model parameters can significantly influence these biases and affect the study's conclusion on both datasets. Finally, we discuss the complexity of accurately labeling local music, emphasizing the risk of misleading conclusions due to unreliable, biased, or incomplete labels. To encourage further research and ensure reproducibility, we have publicly shared our dataset and code.
Event Extraction for Portuguese: A QA-driven Approach using ACE-2005
Cunha, Luís Filipe, Campos, Ricardo, Jorge, Alípio
Event extraction is an Information Retrieval task that commonly consists of identifying the central word for the event (trigger) and the event's arguments. This task has been extensively studied for English but lags behind for Portuguese, partly due to the lack of task-specific annotated corpora. This paper proposes a framework in which two separated BERT-based models were fine-tuned to identify and classify events in Portuguese documents. We decompose this task into two sub-tasks. Firstly, we use a token classification model to detect event triggers. To extract event arguments, we train a Question Answering model that queries the triggers about their corresponding event argument roles. Given the lack of event annotated corpora in Portuguese, we translated the original version of the ACE-2005 dataset (a reference in the field) into Portuguese, producing a new corpus for Portuguese event extraction. To accomplish this, we developed an automatic translation pipeline. Our framework obtains F1 marks of 64.4 for trigger classification and 46.7 for argument classification setting, thus a new state-of-the-art reference for these tasks in Portuguese.
LM-PUB-QUIZ: A Comprehensive Framework for Zero-Shot Evaluation of Relational Knowledge in Language Models
Ploner, Max, Wiland, Jacek, Pohl, Sebastian, Akbik, Alan
Knowledge probing evaluates the extent to which a language model (LM) has acquired relational knowledge during its pre-training phase. It provides a cost-effective means of comparing LMs of different sizes and training setups and is useful for monitoring knowledge gained or lost during continual learning (CL). In prior work, we presented an improved knowledge probe called BEAR (Wiland et al., 2024), which enables the comparison of LMs trained with different pre-training objectives (causal and masked LMs) and addresses issues of skewed distributions in previous probes to deliver a more unbiased reading of LM knowledge. With this paper, we present LM-PUB- QUIZ, a Python framework and leaderboard built around the BEAR probing mechanism that enables researchers and practitioners to apply it in their work. It provides options for standalone evaluation and direct integration into the widely-used training pipeline of the Hugging Face TRANSFORMERS library. Further, it provides a fine-grained analysis of different knowledge types to assist users in better understanding the knowledge in each evaluated LM. We publicly release LM-PUB-QUIZ as an open-source project.
Evaluating Computational Representations of Character: An Austen Character Similarity Benchmark
Yang, Funing, Anderson, Carolyn Jane
Several systems have been developed to extract information about characters to aid computational analysis of English literature. We propose character similarity grouping as a holistic evaluation task for these pipelines. We present AustenAlike, a benchmark suite of character similarities in Jane Austen's novels. Our benchmark draws on three notions of character similarity: a structurally defined notion of similarity; a socially defined notion of similarity; and an expert defined set extracted from literary criticism. We use AustenAlike to evaluate character features extracted using two pipelines, BookNLP and FanfictionNLP. We build character representations from four kinds of features and compare them to the three AustenAlike benchmarks and to GPT-4 similarity rankings. We find that though computational representations capture some broad similarities based on shared social and narrative roles, the expert pairings in our third benchmark are challenging for all systems, highlighting the subtler aspects of similarity noted by human readers.
Ionospheric Scintillation Forecasting Using Machine Learning
Halawa, Sultan, Alansaari, Maryam, Sharif, Maryam, Alhammadi, Amel, Fernini, Ilias
This study explores the use of historical data from Global Navigation Satellite System (GNSS) scintillation monitoring receivers to predict the severity of amplitude scintillation, a phenomenon where electron density irregularities in the ionosphere cause fluctuations in GNSS signal power. These fluctuations can be measured using the S4 index, but real-time data is not always available. The research focuses on developing a machine learning (ML) model that can forecast the intensity of amplitude scintillation, categorizing it into low, medium, or high severity levels based on various time and space-related factors. Among six different ML models tested, the XGBoost model emerged as the most effective, demonstrating a remarkable 77% prediction accuracy when trained with a balanced dataset. This work underscores the effectiveness of machine learning in enhancing the reliability and performance of GNSS signals and navigation systems by accurately predicting amplitude scintillation severity.
BELT-2: Bootstrapping EEG-to-Language representation alignment for multi-task brain decoding
Zhou, Jinzhao, Duan, Yiqun, Chang, Fred, Do, Thomas, Wang, Yu-Kai, Lin, Chin-Teng
The remarkable success of large language models (LLMs) across various multi-modality applications is well established. However, integrating large language models with humans, or brain dynamics, remains relatively unexplored. In this paper, we introduce BELT-2, a pioneering multi-task model designed to enhance both encoding and decoding performance from EEG signals. To bolster the quality of the EEG encoder, BELT-2 is the first work to innovatively 1) adopt byte-pair encoding (BPE)-level EEG-language alignment and 2) integrate multi-task training and decoding in the EEG domain. Inspired by the idea of \textbf{\textit{Bridging the Brain with GPT}}, we further connect the multi-task EEG encoder with LLMs by utilizing prefix-tuning on intermediary output from the EEG encoder. These innovative efforts make BELT-2 a pioneering breakthrough, making it the first work in the field capable of decoding coherent and readable sentences from non-invasive brain signals. Our experiments highlight significant advancements over prior techniques in both quantitative and qualitative measures, achieving a decoding performance with a BLEU-1 score of 52.2\% on the ZuCo dataset. Furthermore, BELT-2 shows a remarkable improvement ranging from 31\% to 162\% on other translation benchmarks. Codes can be accessed via the provided anonymous link~\footnote{https://anonymous.4open.science/r/BELT-2-0048}.
ChartEye: A Deep Learning Framework for Chart Information Extraction
Mustafa, Osama, Ali, Muhammad Khizer, Moetesum, Momina, Siddiqi, Imran
The widespread use of charts and infographics as a means of data visualization in various domains has inspired recent research in automated chart understanding. However, information extraction from chart images is a complex multitasked process due to style variations and, as a consequence, it is challenging to design an end-to-end system. In this study, we propose a deep learning-based framework that provides a solution for key steps in the chart information extraction pipeline. The proposed framework utilizes hierarchal vision transformers for the tasks of chart-type and text-role classification, while YOLOv7 for text detection. The detected text is then enhanced using Super Resolution Generative Adversarial Networks to improve the recognition output of the OCR. Experimental results on a benchmark dataset show that our proposed framework achieves excellent performance at every stage with F1-scores of 0.97 for chart-type classification, 0.91 for text-role classification, and a mean Average Precision of 0.95 for text detection.
Latent Relationship Mining of Glaucoma Biomarkers: a TRI-LSTM based Deep Learning
Huang, Cheng, Shen, Junhao, Luo, Qiuyu, Kooner, Karanjit, Lee, Tsengdar, Liu, Yishen, Zhang, Jia
In recently years, a significant amount of research has been conducted on applying deep learning methods for glaucoma classification and detection. However, the explainability of those established machine learning models remains a big concern. In this research, in contrast, we learn from cognitive science concept and study how ophthalmologists judge glaucoma detection. Simulating experts' efforts, we propose a hierarchical decision making system, centered around a holistic set of carefully designed biomarker-oriented machine learning models. While biomarkers represent the key indicators of how ophthalmologists identify glaucoma, they usually exhibit latent inter-relations. We thus construct a time series model, named TRI-LSTM, capable of calculating and uncovering potential and latent relationships among various biomarkers of glaucoma. Our model is among the first efforts to explore the intrinsic connections among glaucoma biomarkers. We monitor temporal relationships in patients' disease states over time and to capture and retain the progression of disease-relevant clinical information from prior visits, thereby enriching biomarker's potential relationships. Extensive experiments over real-world dataset have demonstrated the effectiveness of the proposed model.
Hierarchical Blockmodelling for Knowledge Graphs
Pietrasik, Marcin, Reformat, Marek, Wilbik, Anna
In this paper, we investigate the use of probabilistic graphical models, specifically stochastic blockmodels, for the purpose of hierarchical entity clustering on knowledge graphs. These models, seldom used in the Semantic Web community, decompose a graph into a set of probability distributions. The parameters of these distributions are then inferred allowing for their subsequent sampling to generate a random graph. In a non-parametric setting, this allows for the induction of hierarchical clusterings without prior constraints on the hierarchy's structure. Specifically, this is achieved by the integration of the Nested Chinese Restaurant Process and the Stick Breaking Process into the generative model. In this regard, we propose a model leveraging such integration and derive a collapsed Gibbs sampling scheme for its inference. To aid in understanding, we describe the steps in this derivation and provide an implementation for the sampler. We evaluate our model on synthetic and real-world datasets and quantitatively compare against benchmark models. We further evaluate our results qualitatively and find that our model is capable of inducing coherent cluster hierarchies in small scale settings. The work presented in this paper provides the first step for the further application of stochastic blockmodels for knowledge graphs on a larger scale. We conclude the paper with potential avenues for future work on more scalable inference schemes.