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Are drones, AI making it harder to fight armed groups in the Sahel?

Al Jazeera

Are drones, AI making it harder to fight armed groups in the Sahel? The brazen attack on the international airport and nearby military airbase in Niamey, Niger's capital, came overnight between January 28 and 29. Balls of orange fire flew across the sky as the Nigerien army attempted to respond while residents ducked for cover and whispered prayers, as shown in videos on social media. ISIL (ISIS) in Sahel Province, or ISSP - a Niger-based outfit earlier known as the ISIL affiliate in the Greater Sahara or ISGS - has since claimed responsibility and says it killed several soldiers, although the Nigerien army disputes this. Many of its fighters had breached military drone hangars using RPGs and mortars, and managed to damage several aircraft and one civilian aeroplane, according to videos from the group.


Three West African juntas have turned to Russia. Now the US wants to engage them

BBC News

Three West African juntas have turned to Russia. The US has declared a stark policy shift towards three West African countries which are battling Islamist insurgents and whose military governments have broken defence ties with France and turned towards Russia. The state department announced that Nick Checker, head of its Bureau of African Affairs, would visit Mali's capital Bamako to convey the United States' respect for Mali's sovereignty and chart a new course in relations, moving past policy missteps. It adds that the US also looks forward to co-operating with Mali's allies, neighbouring Burkina Faso and Niger, on shared security and economic interests. Absent from the agenda is the longstanding American concern for democracy and human rights.


InstructLR: A Scalable Approach to Create Instruction Dataset for Under-Resourced Languages

Keita, Mamadou K., Diarra, Sebastien, Homan, Christopher, Diallo, Seydou

arXiv.org Artificial Intelligence

Effective text generation and chat interfaces for low-resource languages (LRLs) remain a challenge for state-of-the-art large language models (LLMs) to support. This is mainly due to the difficulty of curating high-quality instruction datasets for LRLs, a limitation prevalent in the languages spoken across the African continent and other regions. Current approaches, such as automated translation and synthetic data generation, frequently yield outputs that lack fluency or even orthographic consistency. In this paper, we introduce InstructLR, a novel framework designed to generate high-quality instruction datasets for LRLs. Our approach integrates LLM-driven text generation with a dual-layer quality filtering mechanism: an automated filtering layer based on retrieval-augmented-generation (RAG)-based n-shot prompting, and a human-in-the-loop validation layer. Drawing inspiration from benchmarks such as MMLU in task definition, InstructLR has facilitated the creation of three multi-domain instruction benchmarks: ZarmaInstruct-50k, BambaraInstruct-50k, and FulfuldeInstruct-50k.


US to announce 'substantial' Russia sanctions

BBC News

US to announce'substantial' Russia sanctions The US government will impose a substantial pickup in sanctions against Russia as the fighting in Ukraine continues, according to US Treasury Secretary Scott Bessent. Bessent's comments came just before Nato Secretary-General Mark Rutte was due at the White House, in which he said he hopes to discuss how to deliver Trump's vision of peace in the conflict. Earlier in the day, Rutte said he believes that Trump is the only one who can get this done. At least seven people were killed, including two children, during intense Russian drone and missile strikes on Ukraine - just hours after Trump said plans for a meeting with Vladimir Putin in Budapest had been shelved. Bessent provided no further details on the incoming sanctions, but said they would be announced either after the close this afternoon or first thing tomorrow morning.


VLMs as GeoGuessr Masters: Exceptional Performance, Hidden Biases, and Privacy Risks

Huang, Jingyuan, Huang, Jen-tse, Liu, Ziyi, Liu, Xiaoyuan, Wang, Wenxuan, Zhao, Jieyu

arXiv.org Artificial Intelligence

Visual-Language Models (VLMs) have shown remarkable performance across various tasks, particularly in recognizing geographic information from images. However, significant challenges remain, including biases and privacy concerns. To systematically address these issues in the context of geographic information recognition, we introduce a benchmark dataset consisting of 1,200 images paired with detailed geographic metadata. Evaluating four VLMs, we find that while these models demonstrate the ability to recognize geographic information from images, achieving up to $53.8\%$ accuracy in city prediction, they exhibit significant regional biases. Specifically, performance is substantially higher for economically developed and densely populated regions compared to less developed ($-12.5\%$) and sparsely populated ($-17.0\%$) areas. Moreover, the models exhibit regional biases, frequently overpredicting certain locations; for instance, they consistently predict Sydney for images taken in Australia. The strong performance of VLMs also raises privacy concerns, particularly for users who share images online without the intent of being identified. Our code and dataset are publicly available at https://github.com/uscnlp-lime/FairLocator.


EAP-GP: Mitigating Saturation Effect in Gradient-based Automated Circuit Identification

Zhang, Lin, Dong, Wenshuo, Zhang, Zhuoran, Yang, Shu, Hu, Lijie, Liu, Ninghao, Zhou, Pan, Wang, Di

arXiv.org Artificial Intelligence

Understanding the internal mechanisms of transformer-based language models remains challenging. Mechanistic interpretability based on circuit discovery aims to reverse engineer neural networks by analyzing their internal processes at the level of computational subgraphs. In this paper, we revisit existing gradient-based circuit identification methods and find that their performance is either affected by the zero-gradient problem or saturation effects, where edge attribution scores become insensitive to input changes, resulting in noisy and unreliable attribution evaluations for circuit components. To address the saturation effect, we propose Edge Attribution Patching with GradPath (EAP-GP), EAP-GP introduces an integration path, starting from the input and adaptively following the direction of the difference between the gradients of corrupted and clean inputs to avoid the saturated region. This approach enhances attribution reliability and improves the faithfulness of circuit identification. We evaluate EAP-GP on 6 datasets using GPT-2 Small, GPT-2 Medium, and GPT-2 XL. Experimental results demonstrate that EAP-GP outperforms existing methods in circuit faithfulness, achieving improvements up to 17.7%. Comparisons with manually annotated ground-truth circuits demonstrate that EAP-GP achieves precision and recall comparable to or better than previous approaches, highlighting its effectiveness in identifying accurate circuits.


Grammatical Error Correction for Low-Resource Languages: The Case of Zarma

Keita, Mamadou K., Homan, Christopher, Hamani, Sofiane Abdoulaye, Bremang, Adwoa, Zampieri, Marcos, Alfari, Habibatou Abdoulaye, Ibrahim, Elysabhete Amadou, Owusu, Dennis

arXiv.org Artificial Intelligence

Grammatical error correction (GEC) is important for improving written materials for low-resource languages like Zarma -- spoken by over 5 million people in West Africa. Yet it remains a challenging problem. This study compares rule-based methods, machine translation (MT) models, and large language models (LLMs) for GEC in Zarma. We evaluate each approach's effectiveness on our manually-built dataset of over 250,000 examples using synthetic and human-annotated data. Our experiments show that the MT-based approach using the M2M100 model outperforms others, achieving a detection rate of 95.82% and a suggestion accuracy of 78.90% in automatic evaluations, and scoring 3.0 out of 5.0 in logical/grammar error correction during MEs by native speakers. The rule-based method achieved perfect detection (100%) and high suggestion accuracy (96.27%) for spelling corrections but struggled with context-level errors. LLMs like MT5-small showed moderate performance with a detection rate of 90.62% and a suggestion accuracy of 57.15%. Our work highlights the potential of MT models to enhance GEC in low-resource languages, paving the way for more inclusive NLP tools.


IceCloudNet: 3D reconstruction of cloud ice from Meteosat SEVIRI

Jeggle, Kai, Czerkawski, Mikolaj, Serva, Federico, Saux, Bertrand Le, Neubauer, David, Lohmann, Ulrike

arXiv.org Artificial Intelligence

IceCloudNet is a novel method based on machine learning able to predict high-quality vertically resolved cloud ice water contents (IWC) and ice crystal number concentrations (N$_\textrm{ice}$). The predictions come at the spatio-temporal coverage and resolution of geostationary satellite observations (SEVIRI) and the vertical resolution of active satellite retrievals (DARDAR). IceCloudNet consists of a ConvNeXt-based U-Net and a 3D PatchGAN discriminator model and is trained by predicting DARDAR profiles from co-located SEVIRI images. Despite the sparse availability of DARDAR data due to its narrow overpass, IceCloudNet is able to predict cloud occurrence, spatial structure, and microphysical properties with high precision. The model has been applied to ten years of SEVIRI data, producing a dataset of vertically resolved IWC and N$_\textrm{ice}$ of clouds containing ice with a 3 kmx3 kmx240 mx15 minute resolution in a spatial domain of 30{\deg}W to 30{\deg}E and 30{\deg}S to 30{\deg}N. The produced dataset increases the availability of vertical cloud profiles, for the period when DARDAR is available, by more than six orders of magnitude and moreover, IceCloudNet is able to produce vertical cloud profiles beyond the lifetime of the recently ended satellite missions underlying DARDAR.


Can the US find new partners in West Africa after Niger exit?

Al Jazeera

Following 11 years of defence cooperation and millions of dollars spent on maintaining military bases, the United States officially pulled its troops out of Niger this week in a surprise divorce that experts are calling a "blow" to Washington's ambitions for influence in the troubled Sahel region of West Africa. Once-close relations between the two countries saw the US establish large, expensive military bases from which it launched surveillance drones in Niger to monitor myriad armed groups linked to al-Qaeda and ISIL (ISIS). However, those ties collapsed in March when Niger's military government, which seized power in July 2023, cancelled a decade-long security agreement and told the US, which was pushing for a transition to civilian rule, to remove its 1,100 military personnel stationed there by September 15. For months, the US has failed to either fully align with or outright oppose the ruling military, analysts say. On the one hand, Washington seemed ready to maintain defence relations with the new ruling power, but on the other, it felt compelled to denounce the coup and pause aid to Niger.


Machine learning models for daily rainfall forecasting in Northern Tropical Africa using tropical wave predictors

Satheesh, Athul Rasheeda, Knippertz, Peter, Fink, Andreas H.

arXiv.org Artificial Intelligence

Numerical weather prediction (NWP) models often underperform compared to simpler climatology-based precipitation forecasts in northern tropical Africa, even after statistical postprocessing. AI-based forecasting models show promise but have avoided precipitation due to its complexity. Synoptic-scale forcings like African easterly waves and other tropical waves (TWs) are important for predictability in tropical Africa, yet their value for predicting daily rainfall remains unexplored. This study uses two machine-learning models--gamma regression and a convolutional neural network (CNN)--trained on TW predictors from satellite-based GPM IMERG data to predict daily rainfall during the July-September monsoon season. Predictor variables are derived from the local amplitude and phase information of seven TW from the target and up-and-downstream neighboring grids at 1-degree spatial resolution. The ML models are combined with Easy Uncertainty Quantification (EasyUQ) to generate calibrated probabilistic forecasts and are compared with three benchmarks: Extended Probabilistic Climatology (EPC15), ECMWF operational ensemble forecast (ENS), and a probabilistic forecast from the ENS control member using EasyUQ (CTRL EasyUQ). The study finds that downstream predictor variables offer the highest predictability, with downstream tropical depression (TD)-type wave-based predictors being most important. Other waves like mixed-Rossby gravity (MRG), Kelvin, and inertio-gravity waves also contribute significantly but show regional preferences. ENS forecasts exhibit poor skill due to miscalibration. CTRL EasyUQ shows improvement over ENS and marginal enhancement over EPC15. Both gamma regression and CNN forecasts significantly outperform benchmarks in tropical Africa. This study highlights the potential of ML models trained on TW-based predictors to improve daily precipitation forecasts in tropical Africa.