Physics and Society
New submissions
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New submissions for Mon, 20 May 24
- [1] arXiv:2405.10322 [pdf, ps, other]
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Title: Exploring the Independent Cascade Model and Its Evolution in Social Network Information DiffusionSubjects: Physics and Society (physics.soc-ph); Artificial Intelligence (cs.AI)
This paper delves into the paramount significance of information dissemination within the dynamic realm of social networks. It underscores the pivotal role of information communication models in unraveling the intricacies of data propagation in the digital age. By shedding light on the profound influence of these models, it not only lays the groundwork for exploring various hierarchies and their manifestations but also serves as a catalyst for further research in this formidable field.
- [2] arXiv:2405.10338 [pdf, ps, other]
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Title: Financial Interactions and Capital AccumulationSubjects: Physics and Society (physics.soc-ph); Other Condensed Matter (cond-mat.other); General Economics (econ.GN)
In a series of precedent papers, we have presented a comprehensive methodology, termed Field Economics, for translating a standard economic model into a statistical field-formalism framework. This formalism requires a large number of heterogeneous agents, possibly of different types. It reveals the emergence of collective states among these agents or type of agents while preserving the interactions and microeconomic features of the system at the individual level. In two prior papers, we applied this formalism to analyze the dynamics of capital allocation and accumulation in a simple microeconomic framework of investors and firms.Building upon our prior work, the present paper refines the initial model by expanding its scope. Instead of considering financial firms investing solely in real sectors, we now suppose that financial agents may also invest in other financial firms. We also introduce banks in the system that act as investors with a credit multiplier. Two types of interaction are now considered within the financial sector: financial agents can lend capital to, or choose to buy shares of, other financial firms. Capital now flows between financial agents and is only partly invested in real sectors, depending on their relative returns. We translate this framework into our formalism and study the diffusion of capital and possible defaults in the system, both at the macro and micro level.At the macro level, we find that several collective states may emerge, each characterized by a distinct level of average capital and investors per sector. These collective states depend on external parameters such as level of connections between investors or firms' productivity.The multiplicity of possible collective states is the consequence of the nature of the system composed of interconnected heterogeneous agents. Several equivalent patterns of returns and portfolio allocation may emerge. The multiple collective states induce the unstable nature of financial markets, and some of them include defaults may emerge. At the micro level, we study the propagation of returns and defaults within a given collective state. Our findings highlight the significant role of banks, which can either stabilize the system through lending activities or propagate instability through loans to investors.
- [3] arXiv:2405.10355 [pdf, other]
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Title: Assessing the Impact of Case Correction Methods on the Fairness of COVID-19 Predictive ModelsSubjects: Physics and Society (physics.soc-ph); Computers and Society (cs.CY)
One of the central difficulties of addressing the COVID-19 pandemic has been accurately measuring and predicting the spread of infections. In particular, official COVID-19 case counts in the United States are under counts of actual caseloads due to the absence of universal testing policies. Researchers have proposed a variety of methods for recovering true caseloads, often through the estimation of statistical models on more reliable measures, such as death and hospitalization counts, positivity rates, and demographics. However, given the disproportionate impact of COVID-19 on marginalized racial, ethnic, and socioeconomic groups, it is important to consider potential unintended effects of case correction methods on these groups. Thus, we investigate two of these correction methods for their impact on a downstream COVID-19 case prediction task. For that purpose, we tailor an auditing approach and evaluation protocol to analyze the fairness of the COVID-19 prediction task by measuring the difference in model performance between majority-White counties and majority-minority counties. We find that one of the correction methods improves fairness, decreasing differences in performance between majority-White and majority-minority counties, while the other method increases differences, introducing bias. While these results are mixed, it is evident that correction methods have the potential to exacerbate existing biases in COVID-19 case data and in downstream prediction tasks. Researchers planning to develop or use case correction methods must be careful to consider negative effects on marginalized groups.
- [4] arXiv:2405.10417 [pdf, other]
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Title: Cosmic rays for imaging cultural heritage objectsAuthors: Andrea Giammanco, Marwa Al Moussawi, Matthieu Boone, Tim De Kock, Judy De Roy, Sam Huysmans, Vishal Kumar, Maxime Lagrange, Michael TytgatComments: Submitted to a special issue of iScience about "Cosmic-Ray Muography and Applications"Subjects: Physics and Society (physics.soc-ph); Applied Physics (physics.app-ph)
In cultural heritage conservation, it is increasingly common to rely on non-destructive imaging methods based on the absorption or scattering of photons ($X$ or $\gamma$ rays) or neutrons. However, physical and practical issues limit these techniques: their penetration depth may be insufficient for large and dense objects, they require transporting the objects of interest to dedicated laboratories, artificial radiation is hazardous and may induce activation in the material under study. Muons are elementary particles abundantly and freely produced in cosmic-ray interactions in the atmosphere. Their absorption and scattering in matter are characteristically dependent on the density and elemental composition of the material that they traverse, which offers the possibility of exploiting them for sub-surface remote imaging. This novel technique, nicknamed "muography", has been applied in use cases ranging from geophysics to archaeology to nuclear safety, but it has been so far under-explored for a vast category of cultural heritage objects that are relatively large (from decimeters to human size) and dense (stone, metals). The development of portable muon detectors makes muography particularly competitive in cases where the items to be analysed are not transportable, or set up in a confined environment. This document reviews the relevant literature, presents some exemplary use cases, and critically assesses the strengths and weaknesses of muography in this context.
- [5] arXiv:2405.10450 [pdf, other]
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Title: Quantifying national space heating flexibility potential at high spatial resolution with heating consumption dataSubjects: Physics and Society (physics.soc-ph)
Decarbonizing the building stock in cold countries by replacing fossil fuel boilers with heat pumps is expected to drastically increase electricity demand. While heating flexibility could reduce the impact of additional demand from heat pumps on the power system, characterizing the national spatial distribution of heating flexibility capacity to incorporate into sophisticated power system models is challenging. This paper introduces a novel method for quantifying at large scale and high spatial resolution the energy capacity and duration of heating flexibility in existing building stock based on historical heating consumption and temperature data. This method can reflect the geographic diversity of the national building stock in sophisticated power system models. The proposed heating consumption-based method was tested in Britain using national residential gas data. The results demonstrate the potential of this approach to characterize the heterogeneous distribution of heating flexibility capacity at the national scale. Assuming a 3$^\circ$C temperature flexibility window, a total thermal energy storage capacity of 500 GWh$_{th}$ is identified in the British housing stock. For an illustrative cold weather COP value of 2.5, this thermal energy storage capacity is equivalent to 200 GWh of electricity storage. Regarding heating flexibility duration, gas-heated homes have a median of 5.9 heat-free hours for 20th percentile regional daily winter temperatures from 2010 to 2022. However, extreme cold days nearly halve flexibility duration to a median of 3.6 heat-free hours. These high spatial resolution energy capacity and self-discharge parameters can account for geographic diversity at the national scale and provide a new data-based layer of information for sophisticated power system models to support energy transition.
- [6] arXiv:2405.10665 [pdf, other]
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Title: Leader-Follower Identification with Vehicle-Following Calibration for Non-Lane-Based TrafficAuthors: Mihir Mandar Kulkarni (1), Ankit Anil Chaudhari (2), Karthik K. Srinivasan (3), Bhargava Rama Chilukuri (3), Martin Treiber (2), Ostap Okhrin (2 and 4) ((1) Zachry Department of Civil & Environmental Engineering, Texas A&M University, TAMU, College Station, TX, USA (2) Chair of Econometrics and Statistics esp. in the Transport Sector, Institute of Transport and Economics, Faculty of Transport and Traffic Sciences, Technische Universität Dresden, Dresden, Germany (3) Department of Civil Engineering, Indian Institute of Technology Madras, Chennai, India (4) Center for Scalable Data Analytics and Artificial Intelligence (ScaDS.AI), Dresden/Leipzig, Germany)Subjects: Physics and Society (physics.soc-ph)
Most car-following models were originally developed for lane-based traffic. Over the past two decades, efforts have been made to calibrate car-following models for non-lane-based traffic. However, traffic conditions with varying vehicle dimensions, intermittent following, and multiple leaders often occur and make subjective Leader-Follower (LF) pair identification challenging. In this study, we analyze Vehicle Following (VF) behavior in traffic with a lack of lane discipline using high-resolution microscopic trajectory data collected in Chennai, India. The paper's main contributions are threefold. Firstly, three criteria are used to identify LF pairs from the driver's perspective, taking into account the intermittent following, lack of lane discipline due to consideration of lateral separation, and the presence of in-between vehicles. Second, the psycho-physical concept of the regime in the Wiedemann-99 model is leveraged to determine the traffic-dependent "influence zone" for LF identification. Third, a joint and consistent framework is proposed for identifying LF pairs and estimating VF parameters. The proposed methodology outperforms other heuristic-based LF identification methods from the literature in terms of quantitative and qualitative performance measures. The proposed approach can enable robust and more realistic LF identification and VF parameter calibration with practical applications such as LOS analysis, capacity, and travel time estimation.
- [7] arXiv:2405.10798 [pdf, other]
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Title: Understanding following patterns among high-performance athletesSubjects: Physics and Society (physics.soc-ph)
Professional sports enhance interaction among athletes through training groups, sponsored events and competitions. Among these, the Olympic Games represent the largest competition with a global impact, providing the participants with a unique opportunity for interaction. We studied the following patterns among highly successful athletes to understand the structure of their interactions. We used the list of Olympic medallists in the Tokyo 2020 Games to extract their follower-followee network in Twitter, finding 7,326 connections among 964 athletes. The network displayed frequent connections to similar peers in terms of their features including sex, country and sport. We quantified the influence of these features in the followees choice through a gravity approach capturing the number of connections between homogeneous groups. Our research remarks the importance of datasets built from public exposure of professional athletes, serving as a proxy to investigate interesting aspects of many complex socio-cultural systems at different scales.
Cross-lists for Mon, 20 May 24
- [8] arXiv:2405.09843 (cross-list from econ.TH) [pdf, other]
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Title: Organizational Selection of InnovationComments: 40 pages, 13 figures, 2 tablesSubjects: Theoretical Economics (econ.TH); Multiagent Systems (cs.MA); Physics and Society (physics.soc-ph); Applications (stat.AP)
Budgetary constraints force organizations to pursue only a subset of possible innovation projects. Identifying which subset is most promising is an error-prone exercise, and involving multiple decision makers may be prudent. This raises the question of how to most effectively aggregate their collective nous. Our model of organizational portfolio selection provides some first answers. We show that portfolio performance can vary widely. Delegating evaluation makes sense when organizations employ the relevant experts and can assign projects to them. In most other settings, aggregating the impressions of multiple agents leads to better performance than delegation. In particular, letting agents rank projects often outperforms alternative aggregation rules -- including averaging agents' project scores as well as counting their approval votes -- especially when organizations have tight budgets and can select only a few project alternatives out of many.
Replacements for Mon, 20 May 24
- [9] arXiv:1609.00004 (replaced) [pdf, other]
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Title: On the initial value of PageRankAuthors: Krishanu DeyasiComments: 11 pages, 15 figuresSubjects: Physics and Society (physics.soc-ph); Social and Information Networks (cs.SI)
- [10] arXiv:2402.03894 (replaced) [pdf, other]
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Title: Interpersonal trust: Asymptotic analysis of a stochastic coordination game with multi-agent learningComments: 17 pages, 4 figuresSubjects: Physics and Society (physics.soc-ph); General Economics (econ.GN)
- [11] arXiv:2405.09982 (replaced) [pdf, other]
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Title: Dynamical behavior and optimal control of a stochastic SAIRS epidemic model with two saturated incidencesComments: 18 pages, 5 figuresSubjects: Probability (math.PR); Optimization and Control (math.OC); Physics and Society (physics.soc-ph)
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