South America
Predicting Drug-Drug Interactions using Deep Generative Models on Graphs
Ngo, Nhat Khang, Hy, Truong Son, Kondor, Risi
Latent representations of drugs and their targets produced by contemporary graph autoencoder-based models have proved useful in predicting many types of node-pair interactions on large networks, including drug-drug, drug-target, and target-target interactions. However, most existing approaches model the node's latent spaces in which node distributions are rigid and disjoint; these limitations hinder the methods from generating new links among pairs of nodes. In this paper, we present the effectiveness of variational graph autoencoders (VGAE) in modeling latent node representations on multimodal networks. Our approach can produce flexible latent spaces for each node type of the multimodal graph; the embeddings are used later for predicting links among node pairs under different edge types. To further enhance the models' performance, we suggest a new method that concatenates Morgan fingerprints, which capture the molecular structures of each drug, with their latent embeddings before preceding them to the decoding stage for link prediction. Our proposed model shows competitive results on two multimodal networks: (1) a multi-graph consisting of drug and protein nodes, and (2) a multi-graph consisting of drug and cell line nodes. Our source code is publicly available at https://github.com/HySonLab/drug-interactions.
Partitioned Gradient Matching-based Data Subset Selection for Compute-Efficient Robust ASR Training
Mittal, Ashish, Sivasubramanian, Durga, Iyer, Rishabh, Jyothi, Preethi, Ramakrishnan, Ganesh
Training state-of-the-art ASR systems such as RNN-T often has a high associated financial and environmental cost. Training with a subset of training data could mitigate this problem if the subset selected could achieve on-par performance with training with the entire dataset. Although there are many data subset selection(DSS) algorithms, direct application to the RNN-T is difficult, especially the DSS algorithms that are adaptive and use learning dynamics such as gradients, as RNN-T tend to have gradients with a significantly larger memory footprint. In this paper, we propose Partitioned Gradient Matching (PGM) a novel distributable DSS algorithm, suitable for massive datasets like those used to train RNN-T. Through extensive experiments on Librispeech 100H and Librispeech 960H, we show that PGM achieves between 3x to 6x speedup with only a very small accuracy degradation (under 1% absolute WER difference). In addition, we demonstrate similar results for PGM even in settings where the training data is corrupted with noise.
Leveraging Locality in Abstractive Text Summarization
Liu, Yixin, Ni, Ansong, Nan, Linyong, Deb, Budhaditya, Zhu, Chenguang, Awadallah, Ahmed H., Radev, Dragomir
Neural attention models have achieved significant improvements on many natural language processing tasks. However, the quadratic memory complexity of the self-attention module with respect to the input length hinders their applications in long text summarization. Instead of designing more efficient attention modules, we approach this problem by investigating if models with a restricted context can have competitive performance compared with the memory-efficient attention models that maintain a global context by treating the input as a single sequence. Our model is applied to individual pages which contain parts of inputs grouped by the principle of locality during both encoding and decoding. We empirically investigated three kinds of locality in text summarization at different levels of granularity, ranging from sentences to documents. Our experimental results show that our model has a better performance compared with strong baselines with efficient attention modules, and our analysis provides further insights into our locality-aware modeling strategy.
Explainable Predictive Decision Mining for Operational Support
Park, Gyunam, Kรผsters, Aaron, Tews, Mara, Pitsch, Cameron, Schneider, Jonathan, van der Aalst, Wil M. P.
Several decision points exist in business processes (e.g., whether a purchase order needs a manager's approval or not), and different decisions are made for different process instances based on their characteristics (e.g., a purchase order higher than e500 needs a manager approval). Decision mining in process mining aims to describe/predict the routing of a process instance at a decision point of the process. By predicting the decision, one can take proactive actions to improve the process. For instance, when a bottleneck is developing in one of the possible decisions, one can predict the decision and bypass the bottleneck. However, despite its huge potential for such operational support, existing techniques for decision mining have focused largely on describing decisions but not on predicting them, deploying decision trees to produce logical expressions to explain the decision. In this work, we aim to enhance the predictive capability of decision mining to enable proactive operational support by deploying more advanced machine learning algorithms. Our proposed approach provides explanations of the predicted decisions using SHAP values to support the elicitation of proactive actions. We have implemented a Web application to support the proposed approach and evaluated the approach using the implementation.
Membership Inference Attacks and Generalization: A Causal Perspective
Baluta, Teodora, Shen, Shiqi, Hitarth, S., Tople, Shruti, Saxena, Prateek
Membership inference (MI) attacks highlight a privacy weakness in present stochastic training methods for neural networks. It is not well understood, however, why they arise. Are they a natural consequence of imperfect generalization only? Which underlying causes should we address during training to mitigate these attacks? Towards answering such questions, we propose the first approach to explain MI attacks and their connection to generalization based on principled causal reasoning. We offer causal graphs that quantitatively explain the observed MI attack performance achieved for $6$ attack variants. We refute several prior non-quantitative hypotheses that over-simplify or over-estimate the influence of underlying causes, thereby failing to capture the complex interplay between several factors. Our causal models also show a new connection between generalization and MI attacks via their shared causal factors. Our causal models have high predictive power ($0.90$), i.e., their analytical predictions match with observations in unseen experiments often, which makes analysis via them a pragmatic alternative.
A review of machine learning concepts and methods for addressing challenges in probabilistic hydrological post-processing and forecasting
Papacharalampous, Georgia, Tyralis, Hristos
"Prediction" is a broad and generic term that describes any process for obtaining guesses of unseen variables based on any available information, as well as each of these guesses. On the other hand, "forecasting" is a more specific term that describes any process for issuing predictions for future variables based on information (which most commonly takes the form of time series) about the present and the past, with these particular predictions being broadly called "forecasts". Forecasting is a key theme and topic for this study. Therefore, in what follows, the general focus will be on it and not on prediction in general, although many of the statements and methods that will be referring to it are equally relevant and applicable to other prediction types. The origins of forecasting trace back to the early humans and their pronounced need for certainty in the practical endeavour of supporting their various everyday life decisions (Petropoulos et al. 2022). Thus, forecasting has met until today and still meets numerous implementations, formal and informal. Independently of their exact categorization and features, the formal implementations of forecasting rely, in principal, on concepts, theory and practice that originate from or can be attributed to the predictive branch of statistical modelling, although forecasting is also considered as an entire field on its own because of the major role that the temporal dependence plays in the formulation of its methods. The predictive branch of statistical modelling exhibits profound and fundamental differences with respect to the descriptive and explanatory ones, as it is thoroughly explained in Shmueli (2010).
Climate Nihilism--and Hope--Are Coming From the Strangest Places in Sci-Fi
Sign up to receive the Future Tense newsletter every other Saturday. The U.N.'s COP27 climate summit kicks off on Nov. 6 in Egypt, inviting us, once again, to consider whether we're doing enough, fast enough, to stave off climate chaos and the suffering that will come with it. The scale of change required is head-spinningly drastic, so even unexpectedly rapid expansions in clean energy won't do much to curb malaise and doomsaying. Here in the U.S., the Inflation Reduction Act, the biggest climate investment in the nation's history, has been met, largely, with collective indifference, despite positive buzz about its potential effectiveness. The bill was, predictably, passed without any Republican votes, a grim reminder of the scale of climate denialism.
Summit explores role of ethics in development of artificial intelligence
Universities around the world are taking steps alongside major technology companies to explore ways to bolster ethics education in the artificial intelligence field in line with an initiative supported by the Vatican. The effort seeks to help those already working or aspiring to work in the tech fields understand that the development of artificial intelligence, or AI, should benefit humanity rather than pose uncontrollable challenges to human life. Participants at a global summit at the University of Notre Dame Oct. 25-26 explored ways to encompass ethics education in coursework with speakers calling for widespread integration in both technical and nontechnical curricula. Casey Fiesler, associate professor of information science at the University of Colorado, told in person and online attendees in a session that the long-held view that ethical topics are a "specialization" within technology education must be put aside. "We should not be teaching ethics in the context of computing so that it is completely separate from everything else that we are doing," Fiesler said in calling for a culture shift in higher education that can reach across society.
SUPERB @ SLT 2022: Challenge on Generalization and Efficiency of Self-Supervised Speech Representation Learning
Feng, Tzu-hsun, Dong, Annie, Yeh, Ching-Feng, Yang, Shu-wen, Lin, Tzu-Quan, Shi, Jiatong, Chang, Kai-Wei, Huang, Zili, Wu, Haibin, Chang, Xuankai, Watanabe, Shinji, Mohamed, Abdelrahman, Li, Shang-Wen, Lee, Hung-yi
We present the SUPERB challenge at SLT 2022, which aims at learning self-supervised speech representation for better performance, generalization, and efficiency. The challenge builds upon the SUPERB benchmark and implements metrics to measure the computation requirements of self-supervised learning (SSL) representation and to evaluate its generalizability and performance across the diverse SUPERB tasks. The SUPERB benchmark provides comprehensive coverage of popular speech processing tasks, from speech and speaker recognition to audio generation and semantic understanding. As SSL has gained interest in the speech community and showed promising outcomes, we envision the challenge to uplevel the impact of SSL techniques by motivating more practical designs of techniques beyond task performance. We summarize the results of 14 submitted models in this paper. We also discuss the main findings from those submissions and the future directions of SSL research.
Learning Dependencies of Discrete Speech Representations with Neural Hidden Markov Models
While discrete latent variable models have had great success in self-supervised learning, most models assume that frames are independent. Due to the segmental nature of phonemes in speech perception, modeling dependencies among latent variables at the frame level can potentially improve the learned representations on phonetic-related tasks. In this work, we assume Markovian dependencies among latent variables, and propose to learn speech representations with neural hidden Markov models. Our general framework allows us to compare to self-supervised models that assume independence, while keeping the number of parameters fixed. The added dependencies improve the accessibility of phonetic information, phonetic segmentation, and the cluster purity of phones, showcasing the benefit of the assumed dependencies.