Polarization and Integration in Global AI Research The AI race amplifies security risks and international tensions. While the US restricts mobility and knowledge flows, challenges regulatory efforts to protect its advantage, China leads initiatives of...

Polarization and Integration in Global AI Research arxiv.org/abs/2604.17602

Correcting socioeconomic bias in mobile phone mobility estimates using multilevel regression and poststratification Call detail records (CDR) from mobile phone networks are widely used to study human mobility however CDR data from a single mobile operator are inherently biased because the observed users do not mirr...

Correcting socioeconomic bias in mobile phone mobility estimates using multilevel regression and poststratification arxiv.org/abs/2604.16193

Maximum entropy temporal networks link.aps.org/doi/10.1103/...

Simon's model does not produce Zipf's law: The fundamental rich-get-richer mechanism for any power-law size ranking Many complex systems are composed of disparate, interacting types of varying sizes: Species abundances in ecosystems, firm sizes in markets, city populations in countries, word counts in language, etc...

Simon's model does not produce Zipf's law: The fundamental rich-get-richer mechanism for any power-law size ranking arxiv.org/abs/2604.13184

Forecastability of infectious disease time series: are some seasons and pathogens intrinsically more difficult to forecast? Author summary Could intrinsic properties of an epidemiological time series help explain why a particular season, location, or disease is more difficult to predict in the future? To answer this questi...

Forecastability of infectious disease time series: are some seasons and pathogens intrinsically more difficult to forecast? journals.plos.org/ploscompbiol...

Dozens of AI disease-prediction models were trained on dubious data The models are designed to predict someone’s risk of diabetes or stroke. A few might already have been used on patients.

Dozens of AI disease-prediction models were trained on dubious data idp.nature.com/authorize?re...

Hamiltonian structure and integrability of the susceptible-cleric-zombie-recovered epidemic model link.aps.org/doi/10.1103/...

The parenthood effect in urban mobility We investigate how parenthood and marriage (two major life events) reshape urban mobility patterns, an aspect overlooked in traditional `average citizen' mobility models. Leveraging US census data, we...

The parenthood effect in urban mobility arxiv.org/abs/2501.02299

Nonlinear effects of noise on outbreaks of mosquito-borne diseases Author summary Climate change is expected to cause drastic changes in the spread of mosquito-borne disease outbreaks, both in where they occur and in their size. A key aspect of climate change is an i...

Nonlinear effects of noise on outbreaks of mosquito-borne diseases journals.plos.org/ploscompbiol...

Combining structural modeling and deep learning to calculate the E. coli protein interactome and functional networks idp.nature.com/authorize?re...

The Role of Referrals in Immobility, Inequality, and Inefficiency in Labor Markets We study the consequences of job markets' heavy reliance on referrals. Referrals lead to more opportunities for workers to be hired, which lead to better matches and increased productivity, but also d...

The Role of Referrals in Immobility, Inequality, and Inefficiency in Labor Markets arxiv.org/abs/2012.15753

Analysis of non pharmaceutical interventions with SIR epidemic models: decreasing the infection peak vs. minimizing the epidemic size This study investigates the influence of different types of non-pharmaceutical interventions (NPIs) on epidemic progression using SIR compartmental models. We analyze the optimization of two distinct ...

Analysis of non pharmaceutical interventions with SIR epidemic models: decreasing the infection peak vs. minimizing the epidemic size arxiv.org/abs/2604.08420

Harmonic morphisms and dynamical invariants in network renormalization Renormalization of complex networks requires principled criteria for assessing whether a coarse-graining preserves dynamical content. We prove that discrete harmonic morphisms -- surjective maps prese...

Harmonic morphisms and dynamical invariants in network renormalization arxiv.org/abs/2604.08386

Modeling non-Poissonian temporal hypergraphs by Markovian node dynamics Temporal hypergraphs capture time-resolved group interactions among nodes. Empirical data support that time-stamped group interactions show bursty event sequences and non-trivial temporal correlations...

Modeling non-Poissonian temporal hypergraphs by Markovian node dynamics arxiv.org/abs/2604.07694

Temporal Structure Mediates the Robustness and Collapse of Plant-Pollinator Networks arxiv.org/abs/2604.07347

Measuring the co-evolution of online engagement with (mis)information and its visibility at scale arxiv.org/abs/2506.06106

Ratio of Quantiles Indicates Burstiness with Fewer False Negatives than the Conventional Burstiness Parameter Complexity researchers view burstiness--fluctuating levels of activity--as evidence of hidden interactions within the system generating the activity signal. Yet, current burstiness metrics miss evidence of burstiness in some moderately bursty distributions and under moderate sampling conditions. The canonical Burstiness Parameter (BP) compares distributions of timing statistics to the exponential distribution, representing the timing of independent random events, but it provides false negatives for some parameter ranges of power laws, with and without cut-offs. We introduce a metric that maintains BP's measurement approach but reduces false negatives: the Burstiness Tail-based Index (BTI). Based on ratios of differences in quantiles, BTI correctly classifies bursty distributions over certain parameter ranges misclassified by BP. Additionally, we find BTI to be more robust than BP in the presence of limited sample sizes and short observation windows, using simulated samples drawn from distributions correctly classified by BP in their analytical form. As a case study, we revisit an analysis of human activity data and find that the choice of BTI over BP influences interpretations of the timescales of burstiness in the dataset. Given these analytical, simulated, and empirical results, we argue for BTI's practical advantage over BP in assessing burstiness in real-world temporal signals for complexity research and time series modeling.

Ratio of Quantiles Indicates Burstiness with Fewer False Negatives than the Conventional Burstiness Parameter arxiv.org/abs/2604.05188

An international mega-analysis of psychedelic drug effects on brain circuit function - Nature Medicine Analysis of neuroimaging datasets across five major psychedelics revealed a shared brain signature and provides a comprehensive insight into how these drugs reorganize brain architecture.

An international mega-analysis of psychedelic drug effects on brain circuit function idp.nature.com/authorize?re...

Understanding the complexity of frequency and phase angle fluctuations in power grids Power grids must modernize to meet climate goals while maintaining reliable and stable operating conditions. Yet progress is hindered by a limited understanding of the stochastic processes underlying ...

Understanding the complexity of frequency and phase angle fluctuations in power grids arxiv.org/abs/2604.03133

Premature termination of unemployment benefits increased COVID-19 transmission and deaths in the USA idp.nature.com/authorize?re...

The Retraction Epidemic in Science Across Publishers, Fields, and Countries Retractions serve as an indicator of failures in research integrity, yet most analyses focus on absolute counts rather than risk per paper. We use one of the largest open bibliographic databases to de...

The Retraction Epidemic in Science Across Publishers, Fields, and Countries arxiv.org/abs/2604.02302

Toward AI foundation models for epidemics: Promise, challenges, and paths forward | PNAS Foundation models—large AI systems pretrained on broad, heterogeneous data—are transforming scientific discovery. These models (e.g., GPT, GenCast,...

Toward AI foundation models for epidemics: Promise, challenges, and paths forward www.pnas.org/doi/abs/10.1...

Investigating the replicability of the social and behavioural sciences - Nature A large-scale study on the replicability of claims from social and behavioural science journals reports that about half of the results replicate in the same patterns as the original study.

Investigating the replicability of the social and behavioural sciences idp.nature.com/authorize?re...

Uncovering simultaneous breakthroughs with a robust measure of disruptiveness An embedding-based disruption measure not only robustly captures disruptive works but also reveals simultaneous discoveries.

Uncovering simultaneous breakthroughs with a robust measure of disruptiveness | Science Advances www.science.org/doi/10.1126/...

Multiroute pathogen transmission is different Pathogens can spread via multiple transmission routes. The epidemiology of such pathogens exhibits rich complexity and produces counterintuitive dynamics.

Multiroute pathogen transmission is different | Science Advances www.science.org/doi/10.1126/...

Car Dependency in Urban Accessibility To achieve net-zero emissions, cities must transition away from reliance on private vehicles. However, car-centric urban growth has transformed the automobile from a convenience tool into a necessity ...

Car Dependency in Urban Accessibility arxiv.org/abs/2604.01019

Women's mobility networks enable more efficient travel Our understanding of gender differences in mobility is marked by a clear tension: surveys portray women's movements as more complex than men's, while digital traces suggest less diverse travel. Here, ...

Women's mobility networks enable more efficient travel arxiv.org/abs/2604.00943

Public transport in the 15-minute city The 15-minute city is a powerful planning concept to counter car-dependence by promoting active mobility to amenities and fostering inclusive urban environments. However, this policy has challenges in...

Public transport in the 15-minute city arxiv.org/abs/2604.00699

Simple spatial processes can generate heterogeneous contact distributions in face-to-face interactions Face-to-face interactions reveal recurring patterns, suggesting the possibility of shared underlying mechanisms. More specifically, inter-contact durations, contact durations and number of contacts pe...

Simple spatial processes can generate heterogeneous contact distributions in face-to-face interactions arxiv.org/abs/2604.00652

Mutual Linearity Is a Generic Property of Steady-State Markov Networks link.aps.org/doi/10.1103/...