| Robustness of Regional Matching Scheme over Global Matching Scheme Liang Chen, Naoyuki Tokuda (Utsunomiya University, Japan) | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Robust portfolio selection under Recovery Average Value at Risk Cosimo Munari, Justin Pl\"uckebaum, Stefan Weber | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Robust self-tuning semiparametric PCA for contaminated elliptical distribution Hung Hung, Su-Yun Huang, Shinto Eguchi | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Rollout Algorithms and Approximate Dynamic Programming for Bayesian Optimization and Sequential Estimation Dimitri Bertsekas | L4–5 Advanced | CC-BY | mirrored | 20 pp. | arxiv |
| Roth's Theorem and the Hardy--Littlewood majorant problem for thin subsets of primes Leonidas Daskalakis | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Rough Solutions of the Einstein Constraint Equations David Maxwell | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Rude Stone Monuments in All Countries | L2–5 Introductory | Public domain | mirrored | 566 pp. | wikisource |
| Ruin Probabilities for Risk Processes in Stochastic Networks Hamed Amini, Zhongyuan Cao, Andreea Minca | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Ruin probabilities under general investments and heavy-tailed claims Henrik Hult, Filip Lindskog | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Ruin probability for the quota share model with~phase-type distributed claims Krzysztof Burnecki, Zbigniew Palmowski, Marek Teuerle | L4–5 Advanced | CC-BY | mirrored | 18 pp. | arxiv |
| Rules of Life | L2–5 Introductory | Public domain | mirrored | 23 pp. | wikisource |
| Safe cooperative robot dynamics on graphs Robert Ghrist, Daniel Koditschek | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Safe Subgame Resolving for Extensive Form Correlated Equilibrium Chun Kai Ling, Fei Fang | L4–5 Advanced | CC-BY | mirrored | 13 pp. | arxiv |
| Safety-Aware Hybrid Control of Airborne Wind Energy Systems Nikolaus Vertovec, Sina Ober-Bl\"obaum, Kostas Margellos | L4–5 Advanced | CC-BY | mirrored | 30 pp. | arxiv |
| Sampling random graph homomorphisms and applications to network data analysis Hanbaek Lyu, Facundo Memoli, David Sivakoff | L4–5 Advanced | CC-BY | mirrored | 66 pp. | arxiv |
| Sasaki structures distinguished by their basic Hodge numbers D. Kotschick, G. Placini | L4–5 Advanced | CC-BY-NC-ND | mirrored | 14 pp. | arxiv |
| SATEN: An Object-Oriented Web-Based Revision and Extraction Engine Mary-Anne Williams, Aidan Sims | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Scalable Bayesian transport maps for high-dimensional non-Gaussian spatial fields Matthias Katzfuss, Florian Sch\"afer | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Scalable Estimation for Structured Additive Distributional Regression Nikolaus Umlauf, Johannes Seiler, Mattias Wetscher | L4–5 Advanced | CC-BY | mirrored | 43 pp. | arxiv |
| Scalable Optimal Design of Incremental Volt/VAR Control using Deep Neural Networks Sarthak Gupta, Ali Mehrizi-Sani, Spyros Chatzivasileiadis | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Scalar product and distance in barycentric coordinates Vladimir Zolotov | L4–5 Advanced | CC-BY | mirrored | 7 pp. | arxiv |
| Scale-invariance and contingent claim pricing Jiri Hoogland (CWI, Amsterdam), Dimitri Neumann (CWI | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Scaling analysis of multivariate intermittent time series Robert Kitt, Jaan Kalda | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Scaling and correlation in financial data Rama Cont (CEA Saclay & CNRS Nice) | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Scaling Deep Networks with the Mesh Adaptive Direct Search algorithm Dounia Lakhmiri, Mahdi Zolnouri, Vahid Partovi Nia | L4–5 Advanced | CC-BY | mirrored | 5 pp. | arxiv |
| Scaling in stock market data: stable laws and beyond Rama Cont (1, 2, 3) Marc Potters (2) Jean-Philippe Bouchaud (1 | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Scaling in the distribution of intertrade durations of Chinese stocks Zhi-Qiang Jiang (ECUST), Wei Chen (SZSE), Wei-Xing Zhou (ECUST) | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Scaling invariance in finance II: Path-dependent contingent claims Jiri Hoogland, Dimitri Neumann (CWI, Amsterdam) | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Scaling Laws for the Market Microstructure of the Interdealer Broker Markets David Eliezer, Ian I. Kogan | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Scaling Limit and Renormalisation Group in General (Quantum) Many Body Theory Manfred Requardt | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Scaling limit of the time averaged distribution for continuous time quantum walk and Szegedy's walk on the path Yusuke Ide | L4–5 Advanced | CC0-1.0 | mirrored | 7 pp. | arxiv |
| Scaling Properites of Price Changes for Korean Stock Indices Kyuong Eun Lee, Jae Woo Lee | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Scattering theory and deformations of asymptotically hyperbolic metrics David Borthwick | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| SCC: Nutri 300 (Coppola) | L1–3 Foundational | CC-BY-NC-SA | link only | — | libretexts |
| Scenarios for the Creation of Hyperchaotic Attractors of 3D Maps Aikan Shykhmamedov, Efrosiniia Karatetskaia, Alexey Kazakov | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Schatten class Hankel operators on the Segal-Bargmann space and the Berger-Coburn phenomenon Zhangjian Hu, Jani A. Virtanen | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Schottky's theorem in $\mathbb{C}^n$ P.V.Dovbush | L4–5 Advanced | CC-BY | mirrored | 4 pp. | arxiv |
| Science and Hypothesis | L2–5 Introductory | Public domain | mirrored | 280 pp. | wikisource |
| Science, Physiology, and Nutrition For the Nonscientist Judi S. Morrill | L1–3 Foundational | CC-BY-NC-SA | mirrored | 296 pp. | libretexts |
| Science User Scenarios for a Virtual Observatory Design Reference Mission: Science Requirements for Data Mining Kirk D. Borne | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Scientific Collaboratories as Socio-Technical Interaction Networks: A Theoretical Approach Rob Kling, Geoffrey McKim, Joanna Fortuna | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Score Equivalence for Staged Trees Conor Hughes, Peter Strong, Aditi Shenvi | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Screening Methods for Classification Based on Non-parametric Bayesian Tests Naveed Merchant, Jeffrey D. Hart | L4–5 Advanced | CC-BY-NC-ND | mirrored | 27 pp. | arxiv |
| Search Efficient Binary Network Embedding Daokun Zhang, Jie Yin, Xingquan Zhu | L4–5 Advanced | CC-BY-NC-SA | mirrored | 26 pp. | arxiv |
| Searching for Spaceships David Eppstein | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Seasonality, density dependence and spatial population synchrony Pedro G Nicolau, Sigrunn H S{\o}rbye, Nigel G Yoccoz | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |
| Secondary Kodaira-Spencer classes and nonabelian Dolbeault cohomology Carlos Simpson | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Second Law of Thermodynamics and Macroscopic Observables within Boltzmann's principle, an attempt D.H.E.Gross | L4–5 Advanced | Licence unknown | link only | — | arxiv |
| Second-order accuracy metrics for scoring models and their practical use M.V. Pomazanov | L4–5 Advanced | CC-BY-NC-ND | mirrored | 14 pp. | arxiv |
| Sectoral portfolio optimization by judicious selection of financial ratios via PCA Vrinda Dhingra (1), Amita Sharma (2), Shiv K. Gupta (1) ((1) Indian Institute of Technology | L4–5 Advanced | arxiv-nonexclusive | link only | — | arxiv |