Article
Economics
Paolo Falbo, Carlos Ruiz
Summary: The paper focuses on a typical management problem faced by a large power producer, who has partial influence on the market price. It explores the decision-making process of committing generation to fixed-price bilateral contracts or the spot market, as well as distributing production among different plants. The study formulates a risk management problem by optimizing the profit function with a trade-off between expectation and conditional value at risk. Uncertainties, including demand, renewables generation, and fuel costs, are considered, and the paper also models the futures price to reflect the advantage of the power producer. A MILP formulation is provided, and a simulation using data from the Spanish power market is conducted to analyze the solution.
Article
Mathematics
Catalina Bolance, Carlos Alberto Acuna, Salvador Torra
Summary: This study examines the spatial dependence between risks in stock markets and investigates the impact of systemic risk on financial markets. By using a dynamic Google Trends Uncertainty Index, we propose an alternative definition of neighbors and explore the risk transmission effects during different financial crises. Additionally, a simulation study is conducted to examine the influence of non-normal risk measures and changing number of neighbors on the results.
Article
Economics
Jana Plogmann, Oliver Musshoff, Martin Odening, Matthias Ritter
Summary: This paper investigates the heterogeneity in liquidity of agricultural land markets and explores the effects of returns and price volatility on land sales timing. Non-agricultural investors do not trade land more frequently than farmers. The findings contribute to the discussion on land market regulations and suggest that capping land prices may discourage land sales and decrease land supply.
ECONOMIC MODELLING
(2022)
Article
Business
Zhijie Lin, Xiuzhi Zhang, Ying Zhang
Summary: This research investigates the impact of online advertising on the sales of new houses and identifies contingent factors and the underlying mechanism. The findings suggest that online advertising increases sales, especially in cities with lower housing prices, higher residential incomes, and lower-tier statuses. The mechanism is attributed to price reduction, immigrant attraction, and emigration reduction. Furthermore, it is found that there may not be a spillover effect in the housing market.
ELECTRONIC COMMERCE RESEARCH
(2023)
Article
Dentistry, Oral Surgery & Medicine
Hwee-Ho Kim, Sieun Choi, Young-Il Chang, Won-Jin Yi, Sug-Joon Ahn
Summary: This study developed a three-dimensional statistical shape model (SSM) of normal dentition, which can increase the diagnostic efficiency of orthodontic treatments by providing a visual objective. It can also be used as a 3D template in various fields of dentistry.
CLINICAL ORAL INVESTIGATIONS
(2023)
Article
Computer Science, Information Systems
Gwangsu Lee
Summary: This study utilizes machine learning algorithms to explore predictor variables that determine the impact of national statistical indices managed and announced by the Korean government on the sales of companies listed on KOSPI and KOSDAQ. It also proposes a machine learning algorithm for forecasting the sales of these companies. The findings reveal that different variables in the national statistical indices influence the sales of listed companies in various industries, and the gradient boost algorithm achieves the best performance for forecasting.
Article
Pharmacology & Pharmacy
Chang Yu, Xiang Huang, Hui Nian, Philip He
Summary: The study proposes new weighted log-rank tests to address delayed treatment effects in cancer vaccine or immunotherapy trials. By utilizing NESA for numerical evaluation, the proposed tests demonstrate better performance compared to existing methods, showing close to optimal results in simulations. The methods are further demonstrated in two cancer immunotherapy trials.
PHARMACEUTICAL STATISTICS
(2021)
Article
Forestry
Guven Kaya, Kenan Ok
Summary: This study examined the competitive and cooperative relationships among forest enterprises (FEs) in Turkey during log auction sales of Austrian pine, Scots pine, and fir. Findings showed that FEs may exhibit both competitive and cooperative behaviors with other FEs, regardless of their proximity. Better management of competition and solidarity between FEs can lead to increased revenue without the need to harvest more trees for sustainable forest management.
ANNALS OF FOREST RESEARCH
(2021)
Article
Agricultural Economics & Policy
Guyo Godana Dureti, Martin Paul Tabe-Ojong, Enoch Owusu-Sekyere
Summary: Cluster farming is recognized as a viable means of improving smallholder economic integration and commercialization in developing countries. Our study in Ethiopia shows a positive association between cluster farming and commercialization, regardless of farm scale and crop type. These findings highlight the importance of cluster farming in enhancing smallholder commercialization.
AGRICULTURAL ECONOMICS
(2023)
Article
Economics
Peter Reusens, Frank Vastmans, Sven Damen
Summary: While house price indices struggle to account for changes in house quality, our paper proposes a new framework that quantifies the impact of individual dwelling characteristics on quality change. Using Belgium data, we found substantial improvements in house quality due to energy efficiency upgrades. To avoid overestimating price growth, statistical agencies should incorporate energy performance into house price indices.
ECONOMIC MODELLING
(2023)
Article
Business, Finance
Juan Cabrera, Eleni Gousgounis
Summary: The study found that short sale constraints lead to securities trading at a premium, with opinion dispersion contributing to overpricing. As traders update their valuations over time, opinion dispersion decreases and the impact of overpricing diminishes. Prices under short sale constraints adjust slower and do not fully converge to their fundamental values.
JOURNAL OF FINANCIAL MARKETS
(2021)
Article
Mathematics, Interdisciplinary Applications
Xing-Lu Gao, Ying-Hui Shao, Yan-Hong Yang, Wei-Xing Zhou
Summary: This study investigates the multifractal nature of global grain spot markets and finds that some grain indices exhibit multifractal behavior, calling for further analysis of the complex behaviors in these markets.
CHAOS SOLITONS & FRACTALS
(2022)
Article
Biochemistry & Molecular Biology
Karolina Wanat, Elzbieta Brzezinska
Summary: This study investigates the relationship between a group of active pharmaceutical ingredients and their blood-brain barrier permeability data through statistical analysis and correlation assessment. The results reveal that molecular descriptors such as hydrogen bond acceptors and donors, physiological charge, and energy of the lowest unoccupied molecular orbital play an important role in blood-brain barrier permeability modeling. A log BB regression model is constructed using TLC data through multiple linear regression, which shows good predictive value.
Article
Economics
Sandro Shelegia, Chris M. Wilson
Summary: This paper presents a generalized clearinghouse framework of advertised sales and explores how firm heterogeneity affects market outcomes. It provides original insights into the number and types of firms that use sales, offers new results on market outcomes, extends a common empirical cleaning procedure, and analyzes a family of activities in sales markets.
AMERICAN ECONOMIC JOURNAL-MICROECONOMICS
(2021)
Article
Engineering, Civil
Farman Ali, Zulfiqar Ali, Bing-Zhao Li, Sadia Qamar, Amna Nazeer, Saba Riaz, Muhammad Asif Khan, Rabia Fayyaz, Javeria Nawaz Abbasi
Summary: Drought is a recurrent natural hazard with complex climatic characteristics. This study proposes the simultaneous use of multiple drought measures to accurately monitor regional drought episodes.
WATER RESOURCES MANAGEMENT
(2022)
Article
Physics, Multidisciplinary
Xiaoyu Shi, Jian Zhang, Xia Jiang, Juan Chen, Wei Hao, Bo Wang
Summary: This study presents a novel framework using offline reinforcement learning to improve energy consumption in road transportation. By leveraging real-world human driving trajectories, the proposed method achieves significant improvements in energy consumption. The offline learning approach demonstrates generalizability across different scenarios.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Junhyuk Woo, Soon Ho Kim, Hyeongmo Kim, Kyungreem Han
Summary: Reservoir computing (RC) is a new machine-learning framework that uses an abstract neural network model to process information from complex dynamical systems. This study investigates the neuronal and network dynamics of liquid state machines (LSMs) using numerical simulations and classification tasks. The findings suggest that the computational performance of LSMs is closely related to the dynamic range, with a larger dynamic range resulting in higher performance.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Yuwei Yang, Zhuoxuan Li, Jun Chen, Zhiyuan Liu, Jinde Cao
Summary: This paper proposes an extreme learning machine (ELM) algorithm based on residual correction and Tent chaos sequence (TRELM-DROP) for accurate prediction of traffic flow. The algorithm reduces the impact of randomness in traffic flow through the Tent chaos strategy and residual correction method, and avoids weight optimization using the iterative method. A DROP strategy is introduced to improve the algorithm's ability to predict traffic flow under varying conditions.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Chengwei Dong, Min Yang, Lian Jia, Zirun Li
Summary: This work presents a novel three-dimensional system with multiple types of coexisting attractors, and investigates its dynamics using various methods. The mechanism of chaos emergence is explored, and the periodic orbits in the system are studied using the variational method. A symbolic coding method is successfully established to classify the short cycles. The flexibility and validity of the system are demonstrated through analogous circuit implementation. Various chaos-based applications are also presented to show the system's feasibility.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Viorel Badescu
Summary: This article discusses the maximum work extraction from confined particles energy, considering both reversible and irreversible processes. The results vary for different types of particles and conditions. The concept of exergy cannot be defined for particles that undergo spontaneous creation and annihilation. It is also noted that the Carnot efficiency is not applicable to the conversion of confined thermal radiation into work.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
P. M. Centres, D. J. Perez-Morelo, R. Guzman, L. Reinaudi, M. C. Gimenez
Summary: In this study, a phenomenological investigation of epidemic spread was conducted using a model of agent diffusion over a square region based on the SIR model. Two possible contagion mechanisms were considered, and it was observed that the number of secondary infections produced by an individual during its infectious period depended on various factors.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Zuan Jin, Minghui Ma, Shidong Liang, Hongguang Yao
Summary: This study proposes a differential variable speed limit (DVSL) control strategy considering lane assignment, which sets dynamic speed limits for each lane to attract vehicle lane-changing behaviors before the bottleneck and reduce the impact of traffic capacity drop. Experimental results show that the proposed DVSL control strategy can alleviate traffic congestion and improve efficiency.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Matthew Dicks, Andrew Paskaramoorthy, Tim Gebbie
Summary: In this study, we investigate the learning dynamics of a single reinforcement learning optimal execution trading agent when it interacts with an event-driven agent-based financial market model. The results show that the agents with smaller state spaces converge faster and are able to intuitively learn to trade using spread and volume states. The introduction of the learning agent has a robust impact on the moments of the model, except for the Hurst exponent, which decreases, and it can increase the micro-price volatility as trading volumes increase.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Zhouzhou Yao, Xianyu Wu, Yang Yang, Ning Li
Summary: This paper developed a cooperative lane-changing decision system based on digital technology and indirect reciprocity. By introducing image scoring and a Q-learning based reinforcement learning algorithm, drivers can continuously evaluate gains and adjust their strategies. The study shows that this decision system can improve driver cooperation and traffic efficiency, achieving over 50% cooperation probability under any connected vehicles penetration and traffic density, and reaching 100% cooperation probability under high penetration and medium to high traffic density.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Josephine Nanyondo, Henry Kasumba
Summary: This paper presents a multi-class Aw-Rascle (AR) model with area occupancy expressed in terms of vehicle class proportions. The qualitative properties of the proposed equilibrium velocity and the stability conditions of the model are established. The numerical results show the effect of proportional densities on the flow of vehicle classes, indicating the realism of the proposed model.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Oliver Smirnov
Summary: This study proposes a new method for simultaneously estimating the parameters of the 2D Ising model. The method solves a constrained optimization problem, where the objective function is a pseudo-log-likelihood and the constraint is the Hamiltonian of the external field. Monte Carlo simulations were conducted using models of different shapes and sizes to evaluate the performance of the method with and without the Hamiltonian constraint. The results demonstrate that the proposed estimation method yields lower variance across all model shapes and sizes compared to a simple pseudo-maximum likelihood.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Przemyslaw Chelminiak
Summary: The study investigates the first-passage properties of a non-linear diffusion equation with diffusivity dependent on the concentration/probability density through a power-law relationship. The survival probability and first-passage time distribution are determined based on the power-law exponent, and both exact and approximate expressions are derived, along with their asymptotic representations. The results pertain to diffusing particles that are either freely or harmonically trapped. The mean first-passage time is finite for the harmonically trapped particle, while it is divergent for the freely diffusing particle.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Hidemaro Suwa
Summary: The choice of transition kernel is crucial for the performance of the Markov chain Monte Carlo method. A one-parameter rejection control transition kernel is proposed, and it is shown that the rejection process plays a significant role in determining the sampling efficiency.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)
Article
Physics, Multidisciplinary
Xudong Wang, Yao Chen
Summary: This article investigates the joint influence of expanding medium and constant force on particle diffusion. By starting from the Langevin picture and introducing the effect of external force in two different ways, two models with different force terms are obtained. Detailed analysis and derivation yield the Fokker-Planck equations and moments for the two models. The sustained force behaves as a decoupled force, while the intermittent force changes the diffusion behavior with specific effects depending on the expanding rate of the medium.
PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS
(2024)