215,101 results on '"Anastasia, A"'
Search Results
2. A Finding the Law Online (FLO) party in third class
- Author
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Stepanovic, Anastasia
- Published
- 2024
3. The Effect of Scheduling and Preemption on the Efficiency of LLM Inference Serving
- Author
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Kim, Kyoungmin, Hong, Kijae, Gulcehre, Caglar, and Ailamaki, Anastasia
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Computer Science - Performance ,Computer Science - Artificial Intelligence - Abstract
The growing usage of Large Language Models (LLMs) highlights the demands and challenges in scalable LLM inference systems, affecting deployment and development processes. On the deployment side, there is a lack of comprehensive analysis on the conditions under which a particular scheduler performs better or worse, with performance varying substantially across different schedulers, hardware, models, and workloads. Manually testing each configuration on GPUs can be prohibitively expensive. On the development side, unpredictable performance and unknown upper limits can lead to inconclusive trial-and-error processes, consuming resources on ideas that end up ineffective. To address these challenges, we introduce INFERMAX, an analytical framework that uses inference cost models to compare various schedulers, including an optimal scheduler formulated as a constraint satisfaction problem (CSP) to establish an upper bound on performance. Our framework offers in-depth analysis and raises essential questions, challenging assumptions and exploring opportunities for more efficient scheduling. Notably, our findings indicate that preempting requests can reduce GPU costs by 30% compared to avoiding preemptions at all. We believe our methods and insights will facilitate the cost-effective deployment and development of scalable, efficient inference systems and pave the way for cost-based scheduling.
- Published
- 2024
4. Quantum Error Mitigation via Linear-Depth Verifier Circuits
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Mingare, Angus, Moroz, Anastasia, Kovacs, Marcell D, and Green, Andrew G
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Quantum Physics - Abstract
Implementing many important sub-circuits on near-term quantum devices remains a challenge due to the high levels of noise and the prohibitive depth on standard nearest-neighbour topologies. Overcoming these barriers will likely require quantum error mitigation (QEM) strategies. This work introduces the notion of efficient, high-fidelity verifier circuit architectures that we propose for use in such a QEM scheme. We provide a method for constructing verifier circuits for any quantum circuit that is accurately represented by a low-dimensional matrix product operator (MPO). We demonstrate our method by constructing explicit verifier circuits for multi-controlled single unitary gates as well as the quantum Fourier transform (QFT). By transpiling the circuits to a 2D array of qubits, we estimate the crossover point where the verifier circuit is shallower than the circuit itself, and hence useful for QEM. We propose a method of in situ QEM using the verifier circuit architecture. We conclude that our approach may be useful for calibrating quantum sub-circuits to counter coherent noise but cannot correct for the incoherent noise present in current devices.
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- 2024
5. Fuzzing Processing Pipelines for Zero-Knowledge Circuits
- Author
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Hochrainer, Christoph, Isychev, Anastasia, Wüstholz, Valentin, and Christakis, Maria
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Computer Science - Software Engineering ,Computer Science - Cryptography and Security ,Computer Science - Programming Languages - Abstract
Zero-knowledge (ZK) protocols have recently found numerous practical applications, such as in authentication, online-voting, and blockchain systems. These protocols are powered by highly complex pipelines that process deterministic programs, called circuits, written in one of many domain-specific programming languages, e.g., Circom, Noir, and others. Logic bugs in circuit-processing pipelines could have catastrophic consequences and cause significant financial and reputational damage. As an example, consider that a logic bug in a ZK pipeline could result in attackers stealing identities or assets. It is, therefore, critical to develop effective techniques for checking their correctness. In this paper, we present the first systematic fuzzing technique for ZK pipelines, which uses metamorphic test oracles to detect critical logic bugs. We have implemented our technique in an open-source tool called Circuzz. We used Circuzz to test four significantly different ZK pipelines and found a total of 16 logic bugs in all pipelines. Due to their critical nature, 15 of our bugs have already been fixed by the pipeline developers.
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- 2024
6. GDP nowcasting with large-scale inter-industry payment data in real time -- A network approach
- Author
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Mantziou, Anastasia, Hotte, Kerstin, Cucuringu, Mihai, and Reinert, Gesine
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Statistics - Applications - Abstract
Real-time economic information is essential for policy-making but difficult to obtain. We introduce a granular nowcasting method for macro- and industry-level GDP using a network approach and data on real-time monthly inter-industry payments in the UK. To this purpose we devise a model which we call an extended generalised network autoregressive (GNAR-ex) model, tailored for networks with time-varying edge weights and nodal time series, that exploits the notion of neighbouring nodes and neighbouring edges. The performance of the model is illustrated on a range of synthetic data experiments. We implement the GNAR-ex model on the payments network including time series information of GDP and payment amounts. To obtain robustness against statistical revisions, we optimise the model over 9 quarterly releases of GDP data from the UK Office for National Statistics. Our GNAR-ex model can outperform baseline autoregressive benchmark models, leading to a reduced forecasting error. This work helps to obtain timely GDP estimates at the aggregate and industry level derived from alternative data sources compared to existing, mostly survey-based, methods. Thus, this paper contributes both, a novel model for networks with nodal time series and time-varying edge weights, and the first network-based approach for GDP nowcasting based on payments data.
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- 2024
7. Prospects for measuring the electron's electric dipole moment with polyatomic molecules in an optical lattice
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Bause, Roman, Balasubramanian, Nithesh, Fikkers, Ties, Prinsen, Eifion H., Steinebach, Kees, Jadbabaie, Arian, Hutzler, Nicholas R., Aucar, I. Agustín, Pašteka, Lukáš F., Borschevsky, Anastasia, and Hoekstra, Steven
- Subjects
Physics - Atomic Physics - Abstract
We present the conceptual design of an experiment to measure the electron's electric dipole moment (eEDM) using $^{138}$BaOH molecules in an optical lattice. The BaOH molecule is laser-coolable and highly sensitive to the eEDM, making it an attractive candidate for such a precision measurement, and capturing it in an optical lattice offers potentially very long coherence times. We study possibilities and limitations of this approach, identify the most crucial limiting factors and ways to overcome them. The proposed apparatus can reach a statistical error of $10^{-30}\,e\,$cm by measuring spin precession on a total number of $5 \times 10^9$ molecules over a span of 120 days.
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- 2024
8. First $D^0+\overline{D}^0$ measurement in heavy-ion collisions at SPS energies with NA61/SHINE
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Merzlaya, Anastasia and Collaboration, the NA61/SHINE
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Nuclear Experiment ,High Energy Physics - Experiment - Abstract
The measurement of open charm meson production provides a tool for the investigation of the properties of the hot and dense matter created in nucleus-nucleus collisions at relativistic energies. In particular, charm mesons are of vivid interest in the context of the study of the nature of the phase-transition between confined hadronic matter and the quark-gluon plasma. Recently, the experimental setup of the NA61/SHINE experiment was upgraded with the high spatial resolution Vertex Detector which enables the reconstruction of secondary vertices from open charm meson decays. In this presentation the first $D^0$ meson yields at the SPS energy regime will be shown. The analysis used the most central 20\% of Xe+La collisions at 150A GeV/c from the data set collected in 2017. This allowed the estimation of the corrected yields (dN/dy) for $D^0+\overline{D}^0$ via its $\pi^{+/-} + K^{-/+}$ decay channel at mid-rapidity in the center-of-mass system. The results will be compared and discussed in the context of several model calculations including statistical and dynamical approaches, Comment: 10 pages, 2 figures SQM2024 proceedings
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- 2024
9. Acoustic wave diffraction by a quadrant of sound-soft scatterers
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Nethercote, Matthew, Kisil, Anastasia, and Assier, Raphael
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Mathematical Physics ,Mathematics - Numerical Analysis ,45E10, 35L05, 76N30 - Abstract
Motivated by research in metamaterials, we consider the challenging problem of acoustic wave scattering by a doubly periodic quadrant of sound-soft scatterers arranged in a square formation, which we have dubbed the quarter lattice. This leads to a Wiener--Hopf equation in two complex variables with three unknown functions for which we can reduce and solve exactly using a new analytic method. After some suitable truncations, the resulting linear system is inverted using elementary matrix arithmetic and the solution can be numerically computed. This solution is also critically compared to a numerical least squares collocation approach and to our previous method where we decomposed the lattice into semi-infinite rows or columns., Comment: 24 pages, 10 figures
- Published
- 2024
10. Exploring the Universe with SNAD: Anomaly Detection in Astronomy
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Volnova, Alina A., Aleo, Patrick D., Lavrukhina, Anastasia, Russeil, Etienne, Semenikhin, Timofey, Gangler, Emmanuel, Ishida, Emille E. O., Kornilov, Matwey V., Korolev, Vladimir, Malanchev, Konstantin, Pruzhinskaya, Maria V., and Sreejith, Sreevarsha
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics ,Computer Science - Human-Computer Interaction ,Computer Science - Machine Learning - Abstract
SNAD is an international project with a primary focus on detecting astronomical anomalies within large-scale surveys, using active learning and other machine learning algorithms. The work carried out by SNAD not only contributes to the discovery and classification of various astronomical phenomena but also enhances our understanding and implementation of machine learning techniques within the field of astrophysics. This paper provides a review of the SNAD project and summarizes the advancements and achievements made by the team over several years., Comment: 14 pages, 4 figures
- Published
- 2024
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11. The Third Konus-Wind Catalog of Short Gamma-Ray bursts
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Lysenko, Alexandra L., Svinkin, Dmitry S., Frederiks, Dmitry D., Ridnaia, Anna V., Tsvetkova, Anastasia E., and Ulanov, Mikhail V.
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Astrophysics - High Energy Astrophysical Phenomena - Abstract
In this catalog, we present the results of a systematic study of 199 short gamma-ray bursts (GRBs) detected by Konus-Wind between 2011 January 1 and 2021 August 31. The catalog extends the Second Catalog of short gamma-ray bursts covering the period 1994-2010 by ten years of data. The resulting Konus-Wind short GRB sample includes 494 bursts. From temporal and spectral analyses of the sample, we provide the burst durations, spectral lags, estimates of the minimum variability time scales, rise and decay times, the results of spectral fits with three model functions, the total energy fluences, and the peak energy fluxes of the bursts. We present statistical distributions of these parameters for the complete set of 494 short gamma-ray bursts detected in 1994-2021. We discuss evidence found for an additional spectral component and the presence of extended emission in a fraction of the short GRBs. Finally, we consider the results in the context of the Type I (merger-origin)/Type II (collapsar-origin) classification, and discuss magnetar giant flare sub-sample., Comment: 15 pages, 8 figures, 8 tables, submitted to PASA
- Published
- 2024
12. Optimizing Large Language Models for Dynamic Constraints through Human-in-the-Loop Discriminators
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Wei, Timothy, Miin, Annabelle, and Miin, Anastasia
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Computer Science - Artificial Intelligence - Abstract
Large Language Models (LLMs) have recently demonstrated impressive capabilities across various real-world applications. However, due to the current text-in-text-out paradigm, it remains challenging for LLMs to handle dynamic and complex application constraints, let alone devise general solutions that meet predefined system goals. Current common practices like model finetuning and reflection-based reasoning often address these issues case-by-case, limiting their generalizability. To address this issue, we propose a flexible framework that enables LLMs to interact with system interfaces, summarize constraint concepts, and continually optimize performance metrics by collaborating with human experts. As a case in point, we initialized a travel planner agent by establishing constraints from evaluation interfaces. Then, we employed both LLM-based and human discriminators to identify critical cases and continuously improve agent performance until the desired outcomes were achieved. After just one iteration, our framework achieved a $7.78\%$ pass rate with the human discriminator (a $40.2\%$ improvement over baseline) and a $6.11\%$ pass rate with the LLM-based discriminator. Given the adaptability of our proposal, we believe this framework can be applied to a wide range of constraint-based applications and lay a solid foundation for model finetuning with performance-sensitive data samples.
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- 2024
13. Are AI Detectors Good Enough? A Survey on Quality of Datasets With Machine-Generated Texts
- Author
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Gritsai, German, Voznyuk, Anastasia, Grabovoy, Andrey, and Chekhovich, Yury
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Computer Science - Computation and Language - Abstract
The rapid development of autoregressive Large Language Models (LLMs) has significantly improved the quality of generated texts, necessitating reliable machine-generated text detectors. A huge number of detectors and collections with AI fragments have emerged, and several detection methods even showed recognition quality up to 99.9% according to the target metrics in such collections. However, the quality of such detectors tends to drop dramatically in the wild, posing a question: Are detectors actually highly trustworthy or do their high benchmark scores come from the poor quality of evaluation datasets? In this paper, we emphasise the need for robust and qualitative methods for evaluating generated data to be secure against bias and low generalising ability of future model. We present a systematic review of datasets from competitions dedicated to AI-generated content detection and propose methods for evaluating the quality of datasets containing AI-generated fragments. In addition, we discuss the possibility of using high-quality generated data to achieve two goals: improving the training of detection models and improving the training datasets themselves. Our contribution aims to facilitate a better understanding of the dynamics between human and machine text, which will ultimately support the integrity of information in an increasingly automated world.
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- 2024
14. Opinion-driven risk perception and reaction in SIS epidemics
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Arango, Marcela Ordorica, Bizyaeva, Anastasia, Levin, Simon A., and Leonard, Naomi Ehrich
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Mathematics - Dynamical Systems ,Physics - Physics and Society ,Quantitative Biology - Populations and Evolution - Abstract
We present and analyze a mathematical model to study the feedback between behavior and epidemic spread in a population that is actively assessing and reacting to risk of infection. In our model, a population dynamically forms an opinion that reflects its willingness to engage in risky behavior (e.g., not wearing a mask in a crowded area) or reduce it (e.g., social distancing). We consider SIS epidemic dynamics in which the contact rate within a population adapts as a function of its opinion. For the new coupled model, we prove the existence of two distinct parameter regimes. One regime corresponds to a low baseline infectiousness, and the equilibria of the epidemic spread are identical to those of the standard SIS model. The other regime corresponds to a high baseline infectiousness, and there is a bistability between two new endemic equilibria that reflect an initial preference towards either risk seeking behavior or risk aversion. We prove that risk seeking behavior increases the steady-state infection level in the population compared to the baseline SIS model, whereas risk aversion decreases it. When a population is highly reactive to extreme opinions, we show how risk aversion enables the complete eradication of infection in the population. Extensions of the model to a network of populations or individuals are explored numerically.
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- 2024
15. Molecular Quantum Control Algorithm Design by Reinforcement Learning
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Pipi, Anastasia, Tao, Xuecheng, Narang, Prineha, and Leibrandt, David R.
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Quantum Physics ,Physics - Atomic Physics ,Physics - Chemical Physics ,Physics - Optics - Abstract
Precision measurements of polyatomic molecules offer an unparalleled paradigm to probe physics beyond the Standard Model. The rich internal structure within these molecules makes them exquisite sensors for detecting fundamental symmetry violations, local position invariance, and dark matter. While trapping and control of diatomic and a few very simple polyatomic molecules have been experimentally demonstrated, leveraging the complex rovibrational structure of more general polyatomics demands the development of robust and efficient quantum control schemes. In this study, we present a general, reinforcement-learning-designed, quantum logic approach to prepare molecular ions in a single, pure quantum state. The reinforcement learning agent optimizes the pulse sequence, each followed by a projective measurement, and probabilistically manipulates the collapse of the quantum system to a single state. The performance of the control algorithm is numerically demonstrated in the case of a CaH$^+$ ion, with up to 96 thermally populated eigenstates and under the disturbance of environmental thermal radiation. We expect that the method developed, with physics-informed learning, will be directly implemented for quantum control of polyatomic molecular ions with densely populated structures, enabling new experimental tests of fundamental theories., Comment: Methods Section included
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- 2024
16. From Feynman diagrams to the amplituhedron: a gentle review
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De, Shounak, Pavlov, Dmitrii, Spradlin, Marcus, and Volovich, Anastasia
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High Energy Physics - Theory - Abstract
In these notes we review, for a mathematical audience, the computation of (tree-level) scattering amplitudes in Yang-Mills theory in detail. In particular we demonstrate explicitly how the same formulas for six-particle NMHV helicity amplitudes are obtained from summing Feynman diagrams and from computing the canonical form of the $n=6, k=1, m=4$ amplituhedron., Comment: solicited contribution to a special volume on Positive Geometry for Le Matematiche; 20 pages, 4 figures
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- 2024
17. Classification of radio backgrounds at cosmic dawn and 21-cm signal confirmation using neural networks
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Sikder, Sudipta, Fialkov, Anastasia, and Barkana, Rennan
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Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
Several ongoing and upcoming radio telescopes aim to detect either the global 21-cm signal or the 21-cm power spectrum. The extragalactic radio background, as detected by ARCADE-2 and LWA-1, suggests a strong radio background from cosmic dawn, which can significantly alter the cosmological 21-cm signal, enhancing both the global signal amplitude and the 21-cm power spectrum. In this paper, we employ an artificial neural network (ANN) to check if there is a radio excess over the Cosmic Microwave Background (CMB) in mock data, and if present, we classify its type into one of two categories, a background from high-redshift radio galaxies or a uniform exotic background from the early Universe. Based on clean data (without observational noise), the ANN can predict the background radiation type with $96\%$ accuracy for the power spectrum and $90\%$ for the global signal. Although observational noise reduces the accuracy, the results remain quite useful. We also apply ANNs to map the relation between the 21-cm power spectrum and the global signal. By reconstructing the global signal using the 21-cm power spectrum, an ANN can estimate the global signal range consistent with an observed power spectrum from SKA-like experiments. Conversely, we show that an ANN can reconstruct the 21-cm power spectrum over a wide range of redshifts and wavenumbers given the global signal over the same redshifts. Such trained networks can potentially serve as a valuable tool for cross-confirmation of the 21-cm signal., Comment: Submitted to MNRAS
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- 2024
18. Gapped magnetic ground state in the spin-liquid candidate $\kappa$-(BEDT-TTF)$_2$Ag$_2$(CN)$_3$ suggested by magnetic spectroscopy
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Pal, Sudip, Miksch, Björn, von Nidda, Hans-Albrecht Krug, Bauernfeind, Anastasia, Scheffler, Marc, Yoshida, Yukihoro, Saito, Gunzi, Kawamoto, Atsushi, Mézière, Cécile, Avarvari, Narcis, Schlueter, John A., Pustogow, Andrej, and Dressel, Martin
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Condensed Matter - Strongly Correlated Electrons - Abstract
The nature of the magnetic ground state of highly frustrated systems remained puzzling to this day. Here, we have performed multifrequency electron spin resonance (ESR) measurements on a putative quantum spin liquid compound $\kappa$-(BEDT-TTF)$_2$Ag$_2$(CN)$_3$, which is a rare example of $S = 1/2$ spins on a triangular lattice. At high temperatures, the spin susceptibility exhibits a weak temperature dependence which can be described by the Heisenberg model with an antiferromagnetic exchange interaction of strength $J/k_B \approx 175$ K. At low temperatures, however, the rapid drop of the static spin susceptibility, together with monotonic decrease of the ESR linewidth indicates that strong singlet correlations develop below a pairing energy scale $T^*$ accompanied by a spin gap. On the other hand, a weak Curie-like spin susceptibility and the angular dependence of the linewidth suggest additional contribution from impurity spins. We propose the gradual formation of spin singlets with an inhomogeneous spin gap at low temperatures.
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- 2024
19. Listening to the Wise Few: Select-and-Copy Attention Heads for Multiple-Choice QA
- Author
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Tulchinskii, Eduard, Kushnareva, Laida, Kuznetsov, Kristian, Voznyuk, Anastasia, Andriiainen, Andrei, Piontkovskaya, Irina, Burnaev, Evgeny, and Barannikov, Serguei
- Subjects
Computer Science - Computation and Language ,Computer Science - Machine Learning - Abstract
A standard way to evaluate the abilities of LLM involves presenting a multiple-choice question and selecting the option with the highest logit as the model's predicted answer. However, such a format for evaluating LLMs has limitations, since even if the model knows the correct answer, it may struggle to select the corresponding letter simply due to difficulties in following this rigid format. To address this, we introduce new scores that better capture and reveal model's underlying knowledge: the Query-Key Score (QK-score), derived from the interaction between query and key representations in attention heads, and the Attention Score, based on attention weights. These scores are extracted from specific \textit{select-and-copy} heads, which show consistent performance across popular Multi-Choice Question Answering (MCQA) datasets. Based on these scores, our method improves knowledge extraction, yielding up to 16\% gain for LLaMA2-7B and up to 10\% for larger models on popular MCQA benchmarks. At the same time, the accuracy on a simple synthetic dataset, where the model explicitly knows the right answer, increases by almost 60\%, achieving nearly perfect accuracy, therefore demonstrating the method's efficiency in mitigating MCQA format limitations. To support our claims, we conduct experiments on models ranging from 7 billion to 70 billion parameters in both zero- and few-shot setups.
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- 2024
20. Deep Unlearn: Benchmarking Machine Unlearning
- Author
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Cadet, Xavier F., Borovykh, Anastasia, Malekzadeh, Mohammad, Ahmadi-Abhari, Sara, and Haddadi, Hamed
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Computer Science - Machine Learning ,Computer Science - Artificial Intelligence - Abstract
Machine unlearning (MU) aims to remove the influence of particular data points from the learnable parameters of a trained machine learning model. This is a crucial capability in light of data privacy requirements, trustworthiness, and safety in deployed models. MU is particularly challenging for deep neural networks (DNNs), such as convolutional nets or vision transformers, as such DNNs tend to memorize a notable portion of their training dataset. Nevertheless, the community lacks a rigorous and multifaceted study that looks into the success of MU methods for DNNs. In this paper, we investigate 18 state-of-the-art MU methods across various benchmark datasets and models, with each evaluation conducted over 10 different initializations, a comprehensive evaluation involving MU over 100K models. We show that, with the proper hyperparameters, Masked Small Gradients (MSG) and Convolution Transpose (CT), consistently perform better in terms of model accuracy and run-time efficiency across different models, datasets, and initializations, assessed by population-based membership inference attacks (MIA) and per-sample unlearning likelihood ratio attacks (U-LiRA). Furthermore, our benchmark highlights the fact that comparing a MU method only with commonly used baselines, such as Gradient Ascent (GA) or Successive Random Relabeling (SRL), is inadequate, and we need better baselines like Negative Gradient Plus (NG+) with proper hyperparameter selection.
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- 2024
21. Representation of Classical Data on Quantum Computers
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Lang, Thomas, Heim, Anja, Dremel, Kilian, Prjamkov, Dimitri, Blaimer, Martin, Firsching, Markus, Papadaki, Anastasia, Kasperl, Stefan, and Fuchs, Theobald OJ
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Quantum Physics ,Computer Science - Data Structures and Algorithms ,81-01 (Primary), 81-08 (Secondary) ,E.2 ,H.3.2 - Abstract
Quantum computing is currently gaining significant attention, not only from the academic community but also from industry, due to its potential applications across several fields for addressing complex problems. For any practical problem which may be tackled using quantum computing, it is imperative to represent the data used onto a quantum computing system. Depending on the application, many different types of data and data structures occur, including regular numbers, higher-dimensional data structures, e.g., n-dimensional images, up to graphs. This report aims to provide an overview of existing methods for representing these data types on gate-based quantum computers., Comment: 16 pages, 2 figures
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- 2024
22. Fast-and-flexible decision-making with modulatory interactions
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Moreno-Morton, Rodrigo, Bizyaeva, Anastasia, Leonard, Naomi Ehrich, and Franci, Alessio
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Mathematics - Dynamical Systems ,37G99 - Abstract
Multi-agent systems in biology, society, and engineering are capable of making decisions through the dynamic interaction of their elements. Nonlinearity of the interactions is key for the speed, robustness, and flexibility of multi-agent decision-making. In this work we introduce modulatory, that is, multiplicative, in contrast to additive, interactions in a nonlinear opinion dynamics model of fast-and-flexible decision-making. The original model is nonlinear because network interactions, although additive, are saturated. Modulatory interactions introduce an extra source of nonlinearity that greatly enriches the model decision-making behavior in a mathematically tractable way. Modulatory interactions are widespread in both biological and social decision-making networks; our model provides new tools to understand the role of these interactions in networked decision-making and to engineer them in artificial systems., Comment: 6 pages, 4 figures, submitted to American Control Conference 2025
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- 2024
23. Self-distributive structures, braces & the Yang-Baxter equation
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Doikou, Anastasia
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Mathematical Physics ,Mathematics - Quantum Algebra ,Quantum Physics - Abstract
The theory of the set-theoretic Yang-Baxter equation is reviewed from a purely algebraic point of view. We recall certain algebraic structures called shelves, racks and quandles. These objects satisfy a self-distributivity condition and lead to solutions of the Yang-Baxter equation. We also recall that non-involutive solutions of the braid equation are obtained from shelf and rack solutions by a suitable parametric twist, whereas all involutive set-theoretic solutions are reduced to the flip map via a parametric twist. The notion of braces is also presented as the suitable algebraic structure associated to involutive set-theoretic solutions. The quantum algebra as well as the integrability of Baxterized involutive set-theoretic solutions is also discussed. The explicit form of the Drinfel'd twist is presented allowing the derivation of general set-theoretic solutions., Comment: 27 pages, LaTex
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- 2024
24. Psychometrics for Hypnopaedia-Aware Machinery via Chaotic Projection of Artificial Mental Imagery
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Chang, Ching-Chun, Gao, Kai, Xu, Shuying, Kordoni, Anastasia, Leckie, Christopher, and Echizen, Isao
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Computer Science - Cryptography and Security ,Computer Science - Artificial Intelligence ,Computer Science - Computer Vision and Pattern Recognition ,Computer Science - Machine Learning - Abstract
Neural backdoors represent insidious cybersecurity loopholes that render learning machinery vulnerable to unauthorised manipulations, potentially enabling the weaponisation of artificial intelligence with catastrophic consequences. A backdoor attack involves the clandestine infiltration of a trigger during the learning process, metaphorically analogous to hypnopaedia, where ideas are implanted into a subject's subconscious mind under the state of hypnosis or unconsciousness. When activated by a sensory stimulus, the trigger evokes conditioned reflex that directs a machine to mount a predetermined response. In this study, we propose a cybernetic framework for constant surveillance of backdoors threats, driven by the dynamic nature of untrustworthy data sources. We develop a self-aware unlearning mechanism to autonomously detach a machine's behaviour from the backdoor trigger. Through reverse engineering and statistical inference, we detect deceptive patterns and estimate the likelihood of backdoor infection. We employ model inversion to elicit artificial mental imagery, using stochastic processes to disrupt optimisation pathways and avoid convergent but potentially flawed patterns. This is followed by hypothesis analysis, which estimates the likelihood of each potentially malicious pattern being the true trigger and infers the probability of infection. The primary objective of this study is to maintain a stable state of equilibrium between knowledge fidelity and backdoor vulnerability.
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- 2024
25. Photometry and kinematics of dwarf galaxies from the Apertif HI survey
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Šiljeg, Barbara, Adams, Elizabeth A. K., Fraternali, Filippo, Hess, Kelley M., Oosterloo, Tom A., Marasco, Antonino, Adebahr, Björn, Dénes, Helga, Lucero, Danielle M., Piña, Pavel E. Mancera, Moss, Vanessa A., Ponomareva, Anastasia A., and van der Hulst, J. M.
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Astrophysics - Astrophysics of Galaxies - Abstract
Context. Understanding the dwarf galaxy population in low density environments is crucial for testing the LCDM cosmological model. The increase in diversity towards low mass galaxies is seen as an increase in the scatter of scaling relations such as the stellar mass-size and the baryonic Tully-Fisher relation (BTFR), and is also demonstrated by recent in-depth studies of an extreme subclass of dwarf galaxies of low surface brightness, but large physical sizes, called ultra-diffuse galaxies (UDGs). Aims. We select galaxies from the Apertif HI survey, and apply a constraint on their i-band absolute magnitude to exclude high mass systems. The sample consists of 24 galaxies, and span HI mass ranges of 8.6 < log ($M_{HI}/M_{Sun}$) < 9.7 and stellar mass range of 8.0 < log ($M_*/M_{Sun}$) < 9.7 (with only three galaxies having log ($M_*/M_{Sun}$) > 9). Methods. We determine the geometrical parameters of the HI and stellar discs, build kinematic models from the HI data using 3DBarolo, and extract surface brightness profiles in g-, r- and i-band from the Pan-STARRS 1 photometric survey. Results. We find that, at fixed stellar mass, our HI selected dwarfs have larger optical effective radii than isolated, optically-selected dwarfs from the literature. We find misalignments between the optical and HI morphologies for some of our sample. For most of our galaxies, we use the HI morphology to determine their kinematics, and we stress that deep optical observations are needed to trace the underlying stellar discs. Standard dwarfs in our sample follow the same BTFR of high-mass galaxies, whereas UDGs are slightly offset towards lower rotational velocities, in qualitative agreement with results from previous studies. Finally, our sample features a fraction (25%) of dwarf galaxies in pairs that is significantly larger with respect to previous estimates based on optical spectroscopic data., Comment: 22 pages, 11 figures, 5 tables. Accepted for publication in A&A
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- 2024
26. On the proper rainbow saturation numbers of cliques, paths, and odd cycles
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Baker, Dustin, Gomez-Leos, Enrique, Halfpap, Anastasia, Heath, Emily, Martin, Ryan R., Miller, Joe, Parker, Alex, Pungello, Hope, Schwieder, Coy, and Veldt, Nick
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Mathematics - Combinatorics - Abstract
Given a graph $H$, we say a graph $G$ is properly rainbow $H$-saturated if there is a proper edge-coloring of $G$ which contains no rainbow copy of $H$, but adding any edge to $G$ makes such an edge-coloring impossible. The proper rainbow saturation number, denoted $\text{sat}^*(n,H)$, is the minimum number of edges in an $n$-vertex rainbow $H$-saturated graph. We determine the proper rainbow saturation number for paths up to an additive constant and asymptotically determine $\text{sat}^*(n,K_4)$. In addition, we bound $\text{sat}^*(n,H)$ when $H$ is a larger clique, tree of diameter at least 4, or odd cycle.
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- 2024
27. Adaptive bias for dissensus in nonlinear opinion dynamics with application to evolutionary division of labor games
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Paine, Tyler M., Bizyaeva, Anastasia, and Benjamin, Michael R.
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Electrical Engineering and Systems Science - Systems and Control ,Computer Science - Multiagent Systems ,Computer Science - Robotics - Abstract
This paper addresses the problem of adaptively controlling the bias parameter in nonlinear opinion dynamics (NOD) to allocate agents into groups of arbitrary sizes for the purpose of maximizing collective rewards. In previous work, an algorithm based on the coupling of NOD with an multi-objective behavior optimization was successfully deployed as part of a multi-robot system in an autonomous task allocation field experiment. Motivated by the field results, in this paper we propose and analyze a new task allocation model that synthesizes NOD with an evolutionary game framework. We prove sufficient conditions under which it is possible to control the opinion state in the group to a desired allocation of agents between two tasks through an adaptive bias using decentralized feedback. We then verify the theoretical results with a simulation study of a collaborative evolutionary division of labor game., Comment: v1) To appear at the 2024 IEEE Conference on Decision and Control (CDC) in Milan, Italy. 8 Pages, 5 Figures. v2) Fixed typo
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- 2024
28. Interpretable Action Recognition on Hard to Classify Actions
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Anichenko, Anastasia, Guerin, Frank, and Gilbert, Andrew
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Computer Science - Computer Vision and Pattern Recognition ,Computer Science - Artificial Intelligence - Abstract
We investigate a human-like interpretable model of video understanding. Humans recognise complex activities in video by recognising critical spatio-temporal relations among explicitly recognised objects and parts, for example, an object entering the aperture of a container. To mimic this we build on a model which uses positions of objects and hands, and their motions, to recognise the activity taking place. To improve this model we focussed on three of the most confused classes (for this model) and identified that the lack of 3D information was the major problem. To address this we extended our basic model by adding 3D awareness in two ways: (1) A state-of-the-art object detection model was fine-tuned to determine the difference between "Container" and "NotContainer" in order to integrate object shape information into the existing object features. (2) A state-of-the-art depth estimation model was used to extract depth values for individual objects and calculate depth relations to expand the existing relations used our interpretable model. These 3D extensions to our basic model were evaluated on a subset of three superficially similar "Putting" actions from the Something-Something-v2 dataset. The results showed that the container detector did not improve performance, but the addition of depth relations made a significant improvement to performance., Comment: 5 pages, This manuscript has been accepted at the Human-inspired Computer Vision (HCV) ECCV 2024 Workshop. arXiv admin note: text overlap with arXiv:2107.05319
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- 2024
29. Social impact of CAVs -- coexistence of machines and humans in the context of route choice
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Jamróz, Grzegorz, Akman, Ahmet Onur, Psarou, Anastasia, Varga, Zoltán Györgi, and Kucharski, Rafał
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Computer Science - Multiagent Systems - Abstract
Suppose in a stable urban traffic system populated only by human driven vehicles (HDVs), a given proportion (e.g. 10%) is replaced by a fleet of Connected and Autonomous Vehicles (CAVs), which share information and pursue a collective goal. Suppose these vehicles are centrally coordinated and differ from HDVs only by their collective capacities allowing them to make more efficient routing decisions before the travel on a given day begins. Suppose there is a choice between two routes and every day each driver makes a decision which route to take. Human drivers maximize their utility. CAVs might optimize different goals, such as the total travel time of the fleet. We show that in this plausible futuristic setting, the strategy CAVs are allowed to adopt may result in human drivers either benefitting or being systematically disadvantaged and urban networks becoming more or less optimal. Consequently, some regulatory measures might become indispensable.
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- 2024
30. Improved Halo Model Calibrations for Mixed Dark Matter Models of Ultralight Axions
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Dome, Tibor, May, Simon, Laguë, Alex, Marsh, David J. E., Johnston, Sarah, Bose, Sownak, Tocher, Alex, and Fialkov, Anastasia
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Astrophysics - Cosmology and Nongalactic Astrophysics - Abstract
We study the implications of relaxing the requirement for ultralight axions to account for all dark matter in the Universe by examining mixed dark matter (MDM) cosmologies with axion fractions $f \leq 0.3$ within the fuzzy dark matter (FDM) window $10^{-25}$ eV $\lesssim m \lesssim 10^{-23}$ eV. Our simulations, using a new MDM gravity solver implemented in AxiREPO, capture wave dynamics across various scales with high accuracy down to redshifts $z\approx 1$. We identify halos with Rockstar using the CDM component and find good agreement of inferred halo mass functions (HMFs) and concentration-mass relations with theoretical models across redshifts $z=1-10$. This justifies our halo finder approach a posteriori as well as the assumptions underlying the MDM halo model AxionHMcode. Using the inferred axion halo mass - cold halo mass relation $M_{\text{a}}(M_{\text{c}})$ and calibrating a generalised smoothing parameter $\alpha$ to our MDM simulations, we present a new version of AxionHMcode. The code exhibits excellent agreement with simulations on scales $k< 20 \ h$ cMpc$^{-1}$ at redshifts $z=1-3.5$ for $f\leq 0.1$ around the fiducial axion mass $m = 10^{-24.5}$ eV $ = 3.16\times 10^{-25}$ eV, with maximum deviations remaining below 10%. For axion fractions $f\leq 0.3$, the model maintains accuracy with deviations under 20% at redshifts $z\approx 1$ and scales $k< 10 \ h$ cMpc$^{-1}$, though deviations can reach up to 30% for higher redshifts when $f=0.3$. Reducing the run-time for a single evaluation of AxionHMcode to below $1$ minute, these results highlight the potential of AxionHMcode to provide a robust framework for parameter sampling across MDM cosmologies in Bayesian constraint and forecast analyses., Comment: 20 pages, 10 figures, 5 Tables, comments welcome
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- 2024
31. Positive co-degree thresholds for spanning structures
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Halfpap, Anastasia and Magnan, Van
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Mathematics - Combinatorics ,05C35 (Primary) - Abstract
The \textit{minimum positive co-degree} of a non-empty $r$-graph $H$, denoted $\delta_{r-1}^+(H)$, is the largest integer $k$ such that if a set $S \subset V(H)$ of size $r-1$ is contained in at least one $r$-edge of $H$, then $S$ is contained in at least $k$ $r$-edges of $H$. Motivated by several recent papers which study minimum positive co-degree as a reasonable notion of minimum degree in $r$-graphs, we consider bounds of $\delta_{r-1}^+(H)$ which will guarantee the existence of various spanning subgraphs in $H$. We precisely determine the minimum positive co-degree threshold for Berge Hamiltonian cycles in $r$-graphs, and asymptotically determine the minimum positive co-degree threshold for loose Hamiltonian cycles in $3$-graphs. For all $r$, we also determine up to an additive constant the minimum positive co-degree threshold for perfect matchings., Comment: 29 pages
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- 2024
32. Affective Computing Has Changed: The Foundation Model Disruption
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Schuller, Björn, Mallol-Ragolta, Adria, Almansa, Alejandro Peña, Tsangko, Iosif, Amin, Mostafa M., Semertzidou, Anastasia, Christ, Lukas, and Amiriparian, Shahin
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Computer Science - Artificial Intelligence ,Computer Science - Computation and Language ,Computer Science - Computers and Society - Abstract
The dawn of Foundation Models has on the one hand revolutionised a wide range of research problems, and, on the other hand, democratised the access and use of AI-based tools by the general public. We even observe an incursion of these models into disciplines related to human psychology, such as the Affective Computing domain, suggesting their affective, emerging capabilities. In this work, we aim to raise awareness of the power of Foundation Models in the field of Affective Computing by synthetically generating and analysing multimodal affective data, focusing on vision, linguistics, and speech (acoustics). We also discuss some fundamental problems, such as ethical issues and regulatory aspects, related to the use of Foundation Models in this research area.
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- 2024
33. Community Fact-Checks Trigger Moral Outrage in Replies to Misleading Posts on Social Media
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Chuai, Yuwei, Sergeeva, Anastasia, Lenzini, Gabriele, and Pröllochs, Nicolas
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Computer Science - Social and Information Networks ,Computer Science - Human-Computer Interaction - Abstract
Displaying community fact-checks is a promising approach to reduce engagement with misinformation on social media. However, how users respond to misleading content emotionally after community fact-checks are displayed on posts is unclear. Here, we employ quasi-experimental methods to causally analyze changes in sentiments and (moral) emotions in replies to misleading posts following the display of community fact-checks. Our evaluation is based on a large-scale panel dataset comprising N=2,225,260 replies across 1841 source posts from X's Community Notes platform. We find that informing users about falsehoods through community fact-checks significantly increases negativity (by 7.3%), anger (by 13.2%), disgust (by 4.7%), and moral outrage (by 16.0%) in the corresponding replies. These results indicate that users perceive spreading misinformation as a violation of social norms and that those who spread misinformation should expect negative reactions once their content is debunked. We derive important implications for the design of community-based fact-checking systems.
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- 2024
34. Rational exponents for cliques
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English, Sean, Halfpap, Anastasia, and Krueger, Robert A.
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Mathematics - Combinatorics ,05C35 - Abstract
Let $\mathrm{ex}(n,H,\mathcal{F})$ be the maximum number of copies of $H$ in an $n$-vertex graph which contains no copy of a graph from $\mathcal{F}$. Thinking of $H$ and $\mathcal{F}$ as fixed, we study the asymptotics of $\mathrm{ex}(n,H,\mathcal{F})$ in $n$. We say that a rational number $r$ is \emph{realizable for $H$} if there exists a finite family $\mathcal{F}$ such that $\mathrm{ex}(n,H,\mathcal{F}) = \Theta(n^r)$. Using randomized algebraic constructions, Bukh and Conlon showed that every rational between $1$ and $2$ is realizable for $K_2$. We generalize their result to show that every rational between $1$ and $t$ is realizable for $K_t$, for all $t \geq 2$. We also determine the realizable rationals for stars and note the connection to a related Sidorenko-type supersaturation problem., Comment: 28 pages, 8 figures
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- 2024
35. Learning Communities from Equilibria of Nonlinear Opinion Dynamics
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Xing, Yu, Bizyaeva, Anastasia, and Johansson, Karl H.
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Electrical Engineering and Systems Science - Systems and Control - Abstract
This paper studies community detection for a nonlinear opinion dynamics model from its equilibria. It is assumed that the underlying network is generated from a stochastic block model with two communities, where agents are assigned with community labels and edges are added independently based on these labels. Agents update their opinions following a nonlinear rule that incorporates saturation effects on interactions. It is shown that clustering based on a single equilibrium can detect most community labels (i.e., achieving almost exact recovery), if the two communities differ in size and link probabilities. When the two communities are identical in size and link probabilities, and the inter-community connections are denser than intra-community ones, the algorithm can achieve almost exact recovery under negative influence weights but fails under positive influence weights. Utilizing fixed point equations and spectral methods, we also propose a detection algorithm based on multiple equilibria, which can detect communities with positive influence weights. Numerical experiments demonstrate the performance of the proposed algorithms.
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- 2024
36. Situated Visualization in Motion for Swimming
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Yao, Lijie, Bezerianos, Anastasia, Vuillemot, Romain, and Isenberg, Petra
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Computer Science - Human-Computer Interaction - Abstract
Competitive sports coverage increasingly includes information on athlete or team statistics and records. Sports video coverage has traditionally embedded representations of this data in fixed locations on the screen, but more recently also attached representations to athletes or other targets in motion. These publicly used representations so far have been rather simple and systematic investigations of the research space of embedded visualizations in motion are still missing. Here we report on our preliminary research in the domain of professional and amateur swimming. We analyzed how visualizations are currently added to the coverage of Olympics swimming competitions and then plan to derive a design space for embedded data representations for swimming competitions. We are currently conducting a crowdsourced survey to explore which kind of swimming-related data general audiences are interested in, in order to identify opportunities for additional visualizations to be added to swimming competition coverage.
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- 2024
37. PRIME: Phase Reversed Interleaved Multi-Echo acquisition enables highly accelerated distortion-free diffusion MRI
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Jun, Yohan, Liu, Qiang, Gong, Ting, Cho, Jaejin, Fujita, Shohei, Yong, Xingwang, Huang, Susie Y, Ning, Lipeng, Yendiki, Anastasia, Rathi, Yogesh, and Bilgic, Berkin
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Physics - Medical Physics ,Electrical Engineering and Systems Science - Image and Video Processing ,Electrical Engineering and Systems Science - Signal Processing - Abstract
Purpose: To develop and evaluate a new pulse sequence for highly accelerated distortion-free diffusion MRI (dMRI) by inserting an additional echo without prolonging TR, when generalized slice dithered enhanced resolution (gSlider) radiofrequency encoding is used for volumetric acquisition. Methods: A phase-reversed interleaved multi-echo acquisition (PRIME) was developed for rapid, high-resolution, and distortion-free dMRI, which includes two echoes where the first echo is for target diffusion-weighted imaging (DWI) acquisition with high-resolution and the second echo is acquired with either 1) lower-resolution for high-fidelity field map estimation, or 2) matching resolution to enable efficient diffusion relaxometry acquisitions. The sequence was evaluated on in vivo data acquired from healthy volunteers on clinical and Connectome 2.0 scanners. Results: In vivo experiments demonstrated that 1) high in-plane acceleration (Rin-plane of 5-fold with 2D partial Fourier) was achieved using the high-fidelity field maps estimated from the second echo, which was made at a lower resolution/acceleration to increase its SNR while matching the effective echo spacing of the first readout, 2) high-resolution diffusion relaxometry parameters were estimated from dual-echo PRIME data using a white matter model of multi-TE spherical mean technique (MTE-SMT), and 3) high-fidelity mesoscale DWI at 550 um isotropic resolution could be obtained in vivo by capitalizing on the high-performance gradients of the Connectome 2.0 scanner. Conclusion: The proposed PRIME sequence enabled highly accelerated, high-resolution, and distortion-free dMRI using an additional echo without prolonging scan time when gSlider encoding is utilized., Comment: 12 figures, 1 table
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- 2024
38. Situated Visualization in Motion
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Yao, Lijie, Bezerianos, Anastasia, and Isenberg, Petra
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Computer Science - Human-Computer Interaction - Abstract
We contribute a first design space on visualizations in motion and the design of a pilot study we plan to run in the fall. Visualizations can be useful in contexts where either the observation is in motion or the whole visualization is moving at various speeds. Imagine, for example, displays attached to an athlete or animal that show data about the wearer -- for example, captured from a fitness tracking band; or a visualization attached to a moving object such as a vehicle or a soccer ball. The ultimate goal of our research is to inform the design of visualizations under motion.
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- 2024
39. Reflections on Visualization in Motion for Fitness Trackers
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Islam, Alaul, Yao, Lijie, Bezerianos, Anastasia, Blascheck, Tanja, He, Tingying, Lee, Bongshin, Vuillemot, Romain, and Isenberg, Petra
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Computer Science - Human-Computer Interaction - Abstract
In this paper, we reflect on our past work towards understanding how to design visualizations for fitness trackers that are used in motion. We have coined the term "visualization in motion" for visualizations that are used in the presence of relative motion between a viewer and the visualization. Here, we describe how visualization in motion is relevant to sports scenarios. We also provide new data on current smartwatch visualizations for sports and discuss future challenges for visualizations in motion for fitness tracker.
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- 2024
40. Exploring Crowdworkers' Perceptions, Current Practices, and Desired Practices Regarding Using Non-Workstation Devices for Crowdwork
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Dutta, Senjuti, Ruoti, Scott, Linder, Rhema, Williams, Alex C., and Kuzminykh, Anastasia
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Computer Science - Human-Computer Interaction - Abstract
Despite a plethora of research dedicated to designing HITs for non-workstations, there is a lack of research looking specifically into workers' perceptions of the suitability of these devices for managing and completing work. In this work, we fill this research gap by conducting an online survey of 148 workers on Amazon Mechanical Turk to explore 1. how crowdworkers currently use their non-workstation devices to complete and manage crowdwork, 2. what challenges they face using those devices, and 3. to what extent they wish they could use those devices if their concerns were addressed. Our results show that workers unanimously favor using a desktop to complete and manage crowdwork. While workers occasionally use smartphones or tablets, they find their suitability marginal at best and have little interest in smart speakers and smartwatches, viewing them as unsuitable for crowdwork. When investigating the reason for these views, we find that the key issue is that non workstation devices lack the tooling necessary to automatically find and accept HITs, tooling that workers view as essential in their efforts to compete with bots in accepting high paying work. To address this problem, we propose a new paradigm for finding, accepting, and completing crowdwork that puts crowdworkers on equal footing with bots in these tasks. We also describe future research directions for tailoring HITs to non workstation devices and definitely answering whether smart speakers and smartwatches have a place in crowdwork.
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- 2024
41. Unveiling the Inter-Related Preferences of Crowdworkers: Implications for Personalized and Flexible Platform Design
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Dutta, Senjuti, Linder, Rhema, Williams, Alex C., Kuzminykh, Anastasia, and Ruoti, Scott
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Computer Science - Human-Computer Interaction - Abstract
Crowdsourcing platforms have traditionally been designed with a focus on workstation interfaces, restricting the flexibility that crowdworkers need. Recognizing this limitation and the need for more adaptable platforms, prior research has highlighted the diverse work processes of crowdworkers, influenced by factors such as device type and work stage. However, these variables have largely been studied in isolation. Our study is the first to explore the interconnected variabilities among these factors within the crowdwork community. Through a survey involving 150 Amazon Mechanical Turk crowdworkers, we uncovered three distinct groups characterized by their interrelated variabilities in key work aspects. The largest group exhibits a reliance on traditional devices, showing limited interest in integrating smartphones and tablets into their work routines. The second-largest group also primarily uses traditional devices but expresses a desire for supportive tools and scripts that enhance productivity across all devices, particularly smartphones and tablets. The smallest group actively uses and strongly prefers non-workstation devices, especially smartphones and tablets, for their crowdworking activities. We translate our findings into design insights for platform developers, discussing the implications for creating more personalized, flexible, and efficient crowdsourcing environments. Additionally, we highlight the unique work practices of these crowdworker clusters, offering a contrast to those of more traditional and established worker groups.
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- 2024
42. Serverless Query Processing with Flexible Performance SLAs and Prices
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Bian, Haoqiong, Geng, Dongyang, Chai, Yunpeng, and Ailamaki, Anastasia
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Computer Science - Databases - Abstract
Serverless query processing has become increasingly popular due to its auto-scaling, high elasticity, and pay-as-you-go pricing. It allows cloud data warehouse (or lakehouse) users to focus on data analysis without the burden of managing systems and resources. Accordingly, in serverless query services, users become more concerned about cost-efficiency under acceptable performance than performance under fixed resources. This poses new challenges for serverless query engine design in providing flexible performance service-level agreements (SLAs) and cost-efficiency (i.e., prices). In this paper, we first define the problem of flexible performance SLAs and prices in serverless query processing and discuss its significance. Then, we envision the challenges and solutions for solving this problem and the opportunities it raises for other database research. Finally, we present PixelsDB, an open-source prototype with three service levels supported by dedicated architectural designs. Evaluations show that PixelsDB reduces resource costs by 65.5% for near-real-world workloads generated by Cloud Analytics Benchmark (CAB) while not violating the pending time guarantees., Comment: 7 pages, 7 figures
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- 2024
43. Library luminaries - Anastasia Stepanovic
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Stepanovic, Anastasia
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- 2024
44. Reliability and Separation Index Analysis of Mathematics Questions Integrated with the Cultural Architecture Framework Using the Rasch Model
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Muh. Fitrah, Anastasia Sofroniou, Ofianto, Loso Judijanto, and Widihastuti
- Abstract
This research uses Rasch model analysis to identify the reliability and separation index of an integrated mathematics test instrument with a cultural architecture structure in measuring students' mathematical thinking abilities. The study involved 357 students from six eighth-grade public junior high schools in Bima. The selection of schools was based on average school exam scores and considered the effectiveness of the learning process that used cultural settings to explore mathematical content. Data analysis was conducted using Microsoft Excel to calculate the content validity of Aiken's index with four experts and the jMetrik software to measure reliability and the separation index. The research results indicate that the mathematics test instrument passed validation by mathematics experts and measurements with a valid content validity level. Rasch model calibration shows a very high level of instrument reliability. Separation analysis on the logit scale indicates the instrument's ability to differentiate students with different ability levels with good homogeneity in the distribution of test items and individual abilities. Scale quality statistics show good item response variability, low error rates and a high separation index. This study has limitations because it focuses solely on multiple-choice questions. Similar research must be conducted using other types of questions (such as those used in PISA, namely openconstructed and closed-constructed questions) and integrating other mathematical materials within relevant cultural architectural structures.
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- 2024
45. Investigating Statistical Predictions with First Graders in Greece
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Anastasia Michalopoulou and Sonia Kafoussi
- Abstract
This paper argues that engaging students in informal statistical reasoning from early school years is essential for the development of statistical understanding. We investigated if and how children aged six-seven years old identified variation in a table of data and made predictions through the design of a teaching experiment. The classroom teaching experiment was comprised of four 45 minutes lessons addressing the understanding and interpretation of data sets. In order to describe students' informal predictive reasoning, we used the framework of "data lenses". More specifically, we analyzed the different types of answers the students produced as they engaged in predictive reasoning during an interview given before and after the teaching experiment. The participation of students in (classroom) and out-of-school (family) communities of practice was also taken into consideration. Our results demonstrate that the students benefited from their learning experience and developed data understanding.
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- 2024
46. How Do Transnational Distance Education Graduate Students Perceive Quality? A Collaborative Autoethnography
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Rebecca E. Heiser, Chrysoula Lazou, Anastasia Mavraki, Maria Psychogiou, Aga Palalas, and Pamela Walsh
- Abstract
Driven by competition amongst higher education institutions, increasing recognition of the benefits of international academic mobility, and the global pandemic, transnational distance education has accelerated in recent years. Despite its many advantages, quality assurance issues can pose significant obstacles to success. Using a collaborative autoethnography approach, this study aimed to conceptualize quality dimensions from the perspectives of three Greek graduate students shaped by their collective experience at an open university in Canada. The findings suggest that quality encompasses accessibility, learner-centred instructional design, social-emotional support, and applying acquired knowledge and skills in local contexts. The significance of this study further illustrates the emerging transnational distance student population and highlights their experiences to inform quality internationalization practices in higher education for all students.
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- 2024
47. Grammar and Expectation in Active Dependency Resolution: Experimental and Modeling Evidence from Norwegian
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Anastasia Kobzeva and Dave Kush
- Abstract
Abstract Filler-gap dependency resolution is often characterized as an active process. We probed the mechanisms that determine where and why comprehenders posit gaps during incremental processing using Norwegian as our test language. First, we investigated why active filler-gap dependency resolution is suspended inside "island" domains like embedded questions in some languages. Processing-based accounts hold that resource limitations prevent gap-filling in embedded questions across languages, while grammar-based accounts predict that active gap-filling is only blocked in languages where embedded questions are grammatical islands. In a self-paced reading study, we find that Norwegian participants exhibit filled-gap effects inside embedded questions, which are not islands in the language. The findings are consistent with grammar-based, but not processing, accounts. Second, we asked if active filler-gap processing can be understood as a special case of probabilistic ambiguity resolution within an "expectation-based" framework. To do so, we tested whether word-by-word surprisal values from a neural language model could predict the location and magnitude of filled-gap effects in our behavioral data. We find that surprisal accurately tracks the location of filled-gap effects but severely underestimates their magnitude. This suggests either that mechanisms above and beyond probabilistic ambiguity resolution are required to fully explain active gap-filling behavior or that surprisal values derived from long-short term memory are not good proxies for humans' incremental expectations during filler-gap resolution.
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- 2024
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48. Efficacy and safety of olezarsen in lowering apolipoprotein C-III and triglycerides in healthy Japanese Americans.
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Karwatowska-Prokopczuk, Ewa, Lesogor, Anastasia, Yan, Jing-He, Hoenlinger, Angelika, Margolskee, Alison, Li, Lu, and Tsimikas, Sotirios
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Antisense oligonucleotide ,ApoC-III ,Cardiovascular disease ,Ethnicity ,Pancreatitis ,Triglycerides ,Adult ,Female ,Humans ,Male ,Middle Aged ,Young Adult ,Apolipoprotein C-III ,Asian ,Double-Blind Method ,Oligonucleotides ,Oligonucleotides ,Antisense ,Triglycerides ,Japan ,United States - Abstract
BACKGROUND: Olezarsen is a GalNAc3-conjugated, hepatic-targeted antisense oligonucleotide that lowers apolipoprotein C-III (apoC-III) and triglyceride levels. The efficacy and safety of olezarsen has not previously been studied in ethnically diverse American populations. The aim of this study is to assess the effect of olezarsen in healthy Japanese Americans. METHODS: A randomized, placebo-controlled, double-blind phase 1 study was performed in 28 healthy Japanese American participants treated with olezarsen in single-ascending doses (SAD; 30, 60, 90 mg) or multiple doses (MD; 60 mg every 4 weeks for 4 doses). The primary, secondary, and exploratory objectives were safety and tolerability, pharmacokinetics, and effects of olezarsen on fasting serum triglycerides and apoC-III, respectively. RESULTS: There were 20 participants (16 active:4 placebo) in the SAD part of the study, and 8 participants (6 active:2 placebo) in the MD part of the study. For the primary endpoint, no serious adverse events or clinically relevant laboratory abnormalities were reported. The majority of olezarsen plasma exposure occurred within 24 h post-dose. In the SAD cohorts at Day 15 the percentage reduction in apoC-III/TG was - 39.4%/ - 17.8%, - 60.8%/ - 52.7%, and - 68.1%/ - 39.2% in the 30, 60 and 90 mg doses, respectively, vs 2.3%/44.5% increases in placebo. In the MD cohort, at Day 92 the percentage reduction in apoC-III/TG was - 81.6/ - 73.8% vs - 17.2/ - 40.8% reduction in placebo. Favorable changes were also present in VLDL-C, apoB and HDL-C. CONCLUSIONS: Single- and multiple-dose administration of olezarsen was safe, was well tolerated, and significantly reduced apoC-III and triglyceride levels in healthy Japanese Americans.
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- 2024
49. Missense variants in CMS22 patients reveal that PREPL has both enzymatic and nonenzymatic functions.
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Monnens, Yenthe, Theodoropoulou, Anastasia, Rosier, Karen, Bhalla, Kritika, Mahy, Alexia, Vanhoutte, Roeland, Meulemans, Sandra, Cavani, Edoardo, Antanasijevic, Aleksandar, Lemmens, Irma, Lee, Jennifer, Spellicy, Catherine, Schroer, Richard, Maselli, Ricardo, Laverty, Chamindra, Agostinis, Patrizia, Pagliarini, David, Verhelst, Steven, Marcaida, Maria, Rochtus, Anne, Dal Peraro, Matteo, and Creemers, John
- Subjects
Endocrinology ,Genetic variation ,Genetics ,Humans ,Mutation ,Missense ,Prolyl Oligopeptidases ,Myasthenic Syndromes ,Congenital ,Male ,Female ,Phenotype ,Serine Endopeptidases ,Mitochondria - Abstract
Congenital myasthenic syndrome-22 (CMS22, OMIM 616224) is a rare genetic disorder caused by deleterious genetic variation in the prolyl endopeptidase-like (PREPL) gene. Previous reports have described patients with deletions and nonsense variants in PREPL, but nothing is known about the effect of missense variants in the pathology of CMS22. In this study, we have functionally characterized missense variants in PREPL from 3 patients with CMS22, all with hallmark phenotypes. Biochemical evaluation revealed that these missense variants do not impair hydrolase activity, thereby challenging the conventional diagnostic criteria and disease mechanism. Structural analysis showed that the variants affect regions most likely involved in intraprotein or protein-protein interactions. Indeed, binding to a selected group of known interactors was differentially reduced for the 3 variants. The importance of nonhydrolytic functions of PREPL was investigated in catalytically inactive PREPL p.Ser559Ala cell lines, which showed that hydrolytic activity of PREPL is needed for normal mitochondrial function but not for regulating AP1-mediated transport in the transgolgi network. In conclusion, these studies showed that CMS22 can be caused not only by deletion and truncation of PREPL but also by missense variants that do not necessarily result in a loss of hydrolytic activity of PREPL.
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- 2024
50. Advancements in APOE and dementia research: Highlights from the 2023 AAIC Advancements: APOE conference.
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Kloske, Courtney, Belloy, Michael, Blue, Elizabeth, Bowman, Gregory, Carrillo, Maria, Chen, Xiaoying, Chiba-Falek, Ornit, Davis, Albert, Paolo, Gilbert, Garretti, Francesca, Gate, David, Golden, Lesley, Heinecke, Jay, Herz, Joachim, Huang, Yadong, Iadecola, Costantino, Johnson, Lance, Kanekiyo, Takahisa, Karch, Celeste, Khvorova, Anastasia, Koppes-den Hertog, Sascha, Lamb, Bruce, Lawler, Paige, Guen, Yann, Litvinchuk, Alexandra, Liu, Chia-Chen, Mahinrad, Simin, Marcora, Edoardo, Marino, Claudia, Michaelson, Danny, Miller, Justin, Morganti, Josh, Narayan, Priyanka, Naslavsky, Michel, Oosthoek, Marlies, Ramachandran, Kapil, Ramakrishnan, Abhirami, Raulin, Ana-Caroline, Robert, Aiko, Saleh, Rasha, Sexton, Claire, Shah, Nilomi, Shue, Francis, Sible, Isabel, Soranno, Andrea, Strickland, Michael, Tcw, Julia, Thierry, Manon, Tsai, Li-Huei, Tuckey, Ryan, Ulrich, Jason, van der Kant, Rik, Wang, Na, Wellington, Cheryl, Weninger, Stacie, Yassine, Hussein, Zhao, Na, Bu, Guojun, Goate, Alison, and Holtzman, David
- Subjects
APOE ,Alzheimers disease ,apolipoprotein E ,conference proceedings ,dementia ,lipids ,microglia ,neuroinflammation ,risk factor ,therapeutics ,vasculature ,Humans ,Apolipoproteins E ,Alzheimer Disease ,Congresses as Topic ,Animals ,Amyloid beta-Peptides ,Dementia ,Biomedical Research - Abstract
INTRODUCTION: The apolipoprotein E gene (APOE) is an established central player in the pathogenesis of Alzheimers disease (AD), with distinct apoE isoforms exerting diverse effects. apoE influences not only amyloid-beta and tau pathologies but also lipid and energy metabolism, neuroinflammation, cerebral vascular health, and sex-dependent disease manifestations. Furthermore, ancestral background may significantly impact the link between APOE and AD, underscoring the need for more inclusive research. METHODS: In 2023, the Alzheimers Association convened multidisciplinary researchers at the AAIC Advancements: APOE conference to discuss various topics, including apoE isoforms and their roles in AD pathogenesis, progress in apoE-targeted therapeutic strategies, updates on disease models and interventions that modulate apoE expression and function. RESULTS: This manuscript presents highlights from the conference and provides an overview of opportunities for further research in the field. DISCUSSION: Understanding apoEs multifaceted roles in AD pathogenesis will help develop targeted interventions for AD and advance the field of AD precision medicine. HIGHLIGHTS: APOE is a central player in the pathogenesis of Alzheimers disease. APOE exerts a numerous effects throughout the brain on amyloid-beta, tau, and other pathways. The AAIC Advancements: APOE conference encouraged discussions and collaborations on understanding the role of APOE.
- Published
- 2024
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