Atlantic Ocean
Neural Fields for Fast and Scalable Interpolation of Geophysical Ocean Variables
Johnson, J. Emmanuel, Lguensat, Redouane, Fablet, Ronan, Cosme, Emmanuel, Sommer, Julien Le
Optimal Interpolation (OI) is a widely used, highly trusted algorithm for interpolation and reconstruction problems in geosciences. With the influx of more satellite missions, we have access to more and more observations and it is becoming more pertinent to take advantage of these observations in applications such as forecasting and reanalysis. With the increase in the volume of available data, scalability remains an issue for standard OI and it prevents many practitioners from effectively and efficiently taking advantage of these large sums of data to learn the model hyperparameters. In this work, we leverage recent advances in Neural Fields (NerFs) as an alternative to the OI framework where we show how they can be easily applied to standard reconstruction problems in physical oceanography. We illustrate the relevance of NerFs for gap-filling of sparse measurements of sea surface height (SSH) via satellite altimetry and demonstrate how NerFs are scalable with comparable results to the standard OI. We find that NerFs are a practical set of methods that can be readily applied to geoscience interpolation problems and we anticipate a wider adoption in the future.
Imputation of Missing Streamflow Data at Multiple Gauging Stations in Benin Republic
Mbuvha, Rendani, Adounkpe, Julien Yise Peniel, Mongwe, Wilson Tsakane, Houngnibo, Mandela, Newlands, Nathaniel, Marwala, Tshilidzi
Streamflow observation data is vital for flood monitoring, agricultural, and settlement planning. However, such streamflow data are commonly plagued with missing observations due to various causes such as harsh environmental conditions and constrained operational resources. This problem is often more pervasive in under-resourced areas such as Sub-Saharan Africa. In this work, we reconstruct streamflow time series data through bias correction of the GEOGloWS ECMWF streamflow service (GESS) forecasts at ten river gauging stations in Benin Republic. We perform bias correction by fitting Quantile Mapping, Gaussian Process, and Elastic Net regression in a constrained training period. We show by simulating missingness in a testing period that GESS forecasts have a significant bias that results in low predictive skill over the ten Beninese stations. Our findings suggest that overall bias correction by Elastic Net and Gaussian Process regression achieves superior skill relative to traditional imputation by Random Forest, k-Nearest Neighbour, and GESS lookup. The findings of this work provide a basis for integrating global GESS streamflow data into operational early-warning decision-making systems (e.g., flood alert) in countries vulnerable to drought and flooding due to extreme weather events.
Deep learning for Lagrangian drift simulation at the sea surface
Botvynko, Daria, Granero-Belinchon, Carlos, Van Gennip, Simon, Benzinou, Abdesslam, Fablet, Ronan
We address Lagrangian drift simulation in geophysical dynamics and explore deep learning approaches to overcome known limitations of state-of-the-art model-based and Markovian approaches in terms of computational complexity and error propagation. We introduce a novel architecture, referred to as DriftNet, inspired from the Eulerian Fokker-Planck representation of Lagrangian dynamics. Numerical experiments for Lagrangian drift simulation at the sea surface demonstrates the relevance of DriftNet w.r.t. state-of-the-art schemes. Benefiting from the fully-convolutional nature of Drift-Net, we explore through a neural inversion how to diagnose modelderived velocities w.r.t. real drifter trajectories.
Ukraine Shares Video Demonstrating How It Shot Down 73 Russian Cruise Missiles
The Ukrainian Ministry of Defense (MOD) has shared footage of what appeared to be an air defense system destroying an object amid reports that Ukraine was able to shoot down more than 70 Russian cruise missiles in one day. Russian forces launched about 100 missiles on Ukraine Tuesday, Ukrinform reported, citing Ukrainian Air Force spokesperson Yuriy Ignat. Russia's previous heaviest attack was on Oct. 10, which involved 84 projectiles. Ukrainian air defenses were able to destroy 73 of the Russian cruise missiles, 10 Iranian-made Shahed 131 or 136 drones as well as one Orion unmanned aerial vehicle (UAV) during the most recent bombardment. "This is how our air defenses shot down 73 cruise missiles today," the MOD said in a post that included footage of what appeared to be an air defense system destroying an object.
Atlas: Few-shot Learning with Retrieval Augmented Language Models
Izacard, Gautier, Lewis, Patrick, Lomeli, Maria, Hosseini, Lucas, Petroni, Fabio, Schick, Timo, Dwivedi-Yu, Jane, Joulin, Armand, Riedel, Sebastian, Grave, Edouard
Large language models have shown impressive few-shot results on a wide range of tasks. However, when knowledge is key for such results, as is the case for tasks such as question answering and fact checking, massive parameter counts to store knowledge seem to be needed. Retrieval augmented models are known to excel at knowledge intensive tasks without the need for as many parameters, but it is unclear whether they work in few-shot settings. In this work we present Atlas, a carefully designed and pre-trained retrieval augmented language model able to learn knowledge intensive tasks with very few training examples. We perform evaluations on a wide range of tasks, including MMLU, KILT and NaturalQuestions, and study the impact of the content of the document index, showing that it can easily be updated. Notably, Atlas reaches over 42% accuracy on Natural Questions using only 64 examples, outperforming a 540B parameters model by 3% despite having 50x fewer parameters.
Large Language Models and the Reverse Turing Test
Large Language Models (LLMs) have been transformative. They are pre-trained foundational models that are self-supervised and can be adapted with fine tuning to a wide range of natural language tasks, each of which previously would have required a separate network model. This is one step closer to the extraordinary versatility of human language. GPT-3 and more recently LaMDA can carry on dialogs with humans on many topics after minimal priming with a few examples. However, there has been a wide range of reactions and debate on whether these LLMs understand what they are saying or exhibit signs of intelligence. This high variance is exhibited in three interviews with LLMs reaching wildly different conclusions. A new possibility was uncovered that could explain this divergence. What appears to be intelligence in LLMs may in fact be a mirror that reflects the intelligence of the interviewer, a remarkable twist that could be considered a Reverse Turing Test. If so, then by studying interviews we may be learning more about the intelligence and beliefs of the interviewer than the intelligence of the LLMs. As LLMs become more capable they may transform the way we interact with machines and how they interact with each other. Increasingly, LLMs are being coupled with sensorimotor devices. LLMs can talk the talk, but can they walk the walk? A road map for achieving artificial general autonomy is outlined with seven major improvements inspired by brain systems. LLMs could be used to uncover new insights into brain function by downloading brain data during natural behaviors.
Follow the Wisdom of the Crowd: Effective Text Generation via Minimum Bayes Risk Decoding
Suzgun, Mirac, Melas-Kyriazi, Luke, Jurafsky, Dan
In open-ended natural-language generation, existing text decoding methods typically struggle to produce text which is both diverse and high-quality. Greedy and beam search are known to suffer from text degeneration and linguistic diversity issues, while temperature, top-k, and nucleus sampling often yield diverse but low-quality outputs. In this work, we present crowd sampling, a family of decoding methods based on Bayesian risk minimization, to address this diversity-quality trade-off. Inspired by the principle of "the wisdom of the crowd," crowd sampling seeks to select a candidate from a pool of candidates that has the least expected risk (i.e., highest expected reward) under a generative model according to a given utility function. Crowd sampling can be seen as a generalization of numerous existing methods, including majority voting, and in practice, it can be used as a drop-in replacement for existing sampling methods. Extensive experiments show that crowd sampling delivers improvements of 3-7 ROUGE and BLEU points across a wide range of tasks, including summarization, data-to-text, translation, and textual style transfer, while achieving new state-of-the-art results on WebNLG and WMT'16.
WANLI: Worker and AI Collaboration for Natural Language Inference Dataset Creation
Liu, Alisa, Swayamdipta, Swabha, Smith, Noah A., Choi, Yejin
A recurring challenge of crowdsourcing NLP datasets at scale is that human writers often rely on repetitive patterns when crafting examples, leading to a lack of linguistic diversity. We introduce a novel approach for dataset creation based on worker and AI collaboration, which brings together the generative strength of language models and the evaluative strength of humans. Starting with an existing dataset, MultiNLI for natural language inference (NLI), our approach uses dataset cartography to automatically identify examples that demonstrate challenging reasoning patterns, and instructs GPT-3 to compose new examples with similar patterns. Machine generated examples are then automatically filtered, and finally revised and labeled by human crowdworkers. The resulting dataset, WANLI, consists of 107,885 NLI examples and presents unique empirical strengths over existing NLI datasets. Remarkably, training a model on WANLI improves performance on eight out-of-domain test sets we consider, including by 11% on HANS and 9% on Adversarial NLI, compared to training on the 4x larger MultiNLI. Moreover, it continues to be more effective than MultiNLI augmented with other NLI datasets. Our results demonstrate the promise of leveraging natural language generation techniques and re-imagining the role of humans in the dataset creation process.
Ukraine seeks naval drones to counter Russian attacks from sea
Ukrainian President Volodymyr Zelenskyy has backed a fundraising campaign to help Ukraine build a naval drone fleet to protect cities against Russian missiles launched from warships on the Black Sea. United24, an initiative Zelenskyy launched to raise charitable donations following Russia's invasion in February, said Ukraine needed 100 drones operating from the sea, each of which costs 10 million hryvnias (around $274,000). The fundraising site said that since the invasion began, Russian has launched over 4,500 missiles into Ukraine and "every fifth strike came from the sea". "We must defend the waters of our seas and peaceful cities from Russian missiles launched from ships," Zelenskyy wrote on the Telegram messaging app on Friday. "Naval drones will also help unblock the corridor for civilian ships transporting grain for the world," he said.
Large Language Models with Controllable Working Memory
Li, Daliang, Rawat, Ankit Singh, Zaheer, Manzil, Wang, Xin, Lukasik, Michal, Veit, Andreas, Yu, Felix, Kumar, Sanjiv
Large language models (LLMs) have led to a series of breakthroughs in natural language processing (NLP), owing to their excellent understanding and generation abilities. Remarkably, what further sets these models apart is the massive amounts of world knowledge they internalize during pretraining. While many downstream applications provide the model with an informational context to aid its performance on the underlying task, how the model's world knowledge interacts with the factual information presented in the context remains under explored. As a desirable behavior, an LLM should give precedence to the context whenever it contains task-relevant information that conflicts with the model's memorized knowledge. This enables model predictions to be grounded in the context, which can then be used to update or correct specific model predictions without frequent retraining. By contrast, when the context is irrelevant to the task, the model should ignore it and fall back on its internal knowledge. In this paper, we undertake a first joint study of the aforementioned two properties, namely controllability and robustness, in the context of LLMs. We demonstrate that state-of-the-art T5 and PaLM (both pretrained and finetuned) could exhibit poor controllability and robustness, which do not scale with increasing model size. As a solution, we propose a novel method - Knowledge Aware FineTuning (KAFT) - to strengthen both controllability and robustness by incorporating counterfactual and irrelevant contexts to standard supervised datasets. Our comprehensive evaluation showcases the utility of KAFT across model architectures and sizes.