scholarly journals Microscopic Modeling of Pedestrian Movement in a Shida Night Market Street Segment: Using Vision and Destination Attractiveness

2021 ◽  
Vol 13 (14) ◽  
pp. 8015
Author(s):  
Yun-Shang Chiou ◽  
Ailyne Yap Bayer
Keyword(s):  
Retail Sector ◽  
Movement Model ◽  
Positive Role ◽  
Pedestrian Movement ◽  
Agent Based ◽  
Field Of Vision ◽  
Destination Attractiveness ◽  
Microscopic Modeling ◽  
Parameter Values ◽  
Night Markets

Research has shown that night markets play a positive role in improving urban sustainability. In Taiwan, many people go to night markets for leisurely strolling and to eat out with family and friends. The variety of food choices is a major reason for visiting. This preference and the shops’ locations affect not only how pedestrians move around but also the business of the night market. Pedestrian vision has been considered in only a minority of studies regarding pedestrian movement in shopping environments. Although some studies have focused on the impulse stops of pedestrians, few have considered “destination attractiveness” and its influence on surrounding shops. This paper aims to improve the pedestrian movement model in night markets with the incorporation of the “destination attractiveness” factor. The proposed microscopy agent-based model, implemented in NetLogo, uses “field of vision” as the possible destinations of the pedestrian’s next movement. Inside the “field of vision”, each shop competes for the pedestrian’s attention based on its “destination attractiveness”. The model’s parameter values were calibrated and the simulation results were verified with real-world observed data with good agreement. The proposed pedestrian movement model can benefit the retail sector by improving customer satisfaction and profitability by enhancing the layout of the facilities.

scholarly journals MARKET STATISTICS OF A PSYCHOLOGY-BASED HETEROGENEOUS AGENT MODEL

2008 ◽  
Vol 11 (07) ◽  
pp. 717-737 ◽  
Author(s):  
HARBIR LAMBA ◽  
TIM SEAMAN
Keyword(s):  
Heterogeneous Agent ◽  
Agent Based ◽  
Agent Model ◽  
Fundamental Parameters ◽  
Market Participants ◽  
Information Stream ◽  
Momentum Trading ◽  
Real Market ◽  
Available Information ◽  
Parameter Values

We continue an investigation into a class of agent-based market models that are motivated by a psychologically-plausible form of bounded rationality. Some of the agents in an otherwise efficient hypothetical market are endowed with differing tolerances to the tension caused by being in the minority. This herding tendency may be due to purely psychological effects, momentum-trading strategies, or the rational response to perverse marketplace incentives. The resulting model has the important properties of being both very simple and insensitive to its small number of fundamental parameters. While it is most certainly a caricature market, with only boundedly rational traders and the globally available information stream being modeled directly, other market participants and effects are indirectly replicated. We show that all of the most important "stylized facts" of real market statistics are reproduced by this model. Another useful aspect of the model is that, for certain parameter values, it reduces to a standard efficient-market system. This allows us to isolate and observe the effects of particular kinds of non-rationality. To this end, we consider the effects of different asymmetries in agent behavior and show that one in particular leads to skew statistics consistent with those seen in some real financial markets.

scholarly journals Testing temporal changes in allele frequencies: a simulation approach

2010 ◽  
Vol 92 (4) ◽  
pp. 309-320 ◽  
Author(s):  
EDSON SANDOVAL-CASTELLANOS
Keyword(s):  
Molecular Data ◽  
Temporal Changes ◽  
Allele Frequencies ◽  
Small Populations ◽  
Simulation Approach ◽  
Simulation Test ◽  
Agent Based ◽  
Binomial Sampling ◽  
Molecular Databases ◽  
Parameter Values

SummaryAnalysis of the temporal variation in allele frequencies is useful for studying microevolutionary processes. However, many statistical methods routinely used to test temporal changes in allele frequencies fail to establish a proper hypothesis or have theoretical or practical limitations. Here, a Bayesian statistical test is proposed in which the distribution of the distances among sampling frequencies is approached with computer simulations, and hypergeometric sampling is considered instead of binomial sampling. To validate the test and compare its performance with other tests, agent-based model simulations were run for a variety of scenarios, and two real molecular databases were analysed. The results showed that the simulation test (ST) maintained the significance value used (α=0·05) for a vast combination of parameter values, whereas other tests were sensitive to the effect of genetic drift or binomial sampling. The differences between binomial and hypergeometric sampling were more complex than expected, and a novel effect was described. This study suggests that the ST is especially useful for studies with small populations and many alleles, as in microsatellite or sequencing molecular data.

scholarly journals Signaling pathways have an inherent need for noise to acquire information

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Eugenio Azpeitia ◽  
Eugenio P. Balanzario ◽  
Andreas Wagner
Keyword(s):  
Signaling Pathways ◽  
Information Acquisition ◽  
Cellular Level ◽  
Kinetic Properties ◽  
Positive Role ◽  
Binding Interactions ◽  
Reversible Binding ◽  
Wide Range ◽  
The One ◽  
Parameter Values

Abstract Background All living systems acquire information about their environment. At the cellular level, they do so through signaling pathways. Such pathways rely on reversible binding interactions between molecules that detect and transmit the presence of an extracellular cue or signal to the cell’s interior. These interactions are inherently stochastic and thus noisy. On the one hand, noise can cause a signaling pathway to produce the same response for different stimuli, which reduces the amount of information a pathway acquires. On the other hand, in processes such as stochastic resonance, noise can improve the detection of weak stimuli and thus the acquisition of information. It is not clear whether the kinetic parameters that determine a pathway’s operation cause noise to reduce or increase the acquisition of information. Results We analyze how the kinetic properties of the reversible binding interactions used by signaling pathways affect the relationship between noise, the response to a signal, and information acquisition. Our results show that, under a wide range of biologically sensible parameter values, a noisy dynamic of reversible binding interactions is necessary to produce distinct responses to different stimuli. As a consequence, noise is indispensable for the acquisition of information in signaling pathways. Conclusions Our observations go beyond previous work by showing that noise plays a positive role in signaling pathways, demonstrating that noise is essential when such pathways acquire information.

scholarly journals xml2jupyter: Mapping parameters between XML and Jupyter widgets

2019 ◽  
Author(s):  
Randy Heiland ◽  
Daniel Mishler ◽  
Tyler Zhang ◽  
Eric Bower ◽  
Paul Macklin
Keyword(s):  
Programming Languages ◽  
Markup Language ◽  
Command Line ◽  
Graphical Interface ◽  
Web Browser ◽  
Agent Based ◽  
Mapping Parameters ◽  
Extensible Markup ◽  
Parameter Values ◽  
Python Package

AbstractJupyter Notebooks [4, 6] provide executable documents (in a variety of programming languages) that can be run in a web browser. When a notebook contains graphical widgets, it becomes an easy-to-use graphical user interface (GUI). Many scientific simulation packages use text-based configuration files to provide parameter values and run at the command line without a graphical interface. Manually editing these files to explore how different values affect a simulation can be burdensome for technical users, and impossible to use for those with other scientific backgrounds. xml2jupyter is a Python package that addresses these scientific bottlenecks. It provides a mapping between configuration files, formatted in the Extensible Markup Language (XML), and Jupyter widgets. Widgets are automatically generated from the XML file and these can, optionally, be incorporated into a larger GUI for a simulation package, and optionally hosted on cloud resources. Users modify parameter values via the widgets, and the values are written to the XML configuration file which is input to the simulation’s command-line interface. xml2jupyter has been tested using PhysiCell [1], an open source, agent-based simulator for biology, and it is being used by students for classroom and research projects. In addition, we use xml2jupyter to help create Jupyter GUIs for PhysiCell-related applications running on nanoHUB [5].

Urban Commercial Vehicle Movement Model for Calgary, Alberta, Canada

2005 ◽  
Vol 1921 (1) ◽  
pp. 1-10 ◽  
Author(s):  
K. J. Stefan ◽  
J. D. P. McMillan ◽  
J. D. Hunt
Keyword(s):  
Monte Carlo ◽  
Commercial Vehicle ◽  
Industrial Area ◽  
Commercial Vehicles ◽  
Movement Model ◽  
Agent Based ◽  
Monte Carlo Techniques ◽  
Vehicle Type ◽  
Vehicle Movement

Commercial vehicle movements compose perhaps 15% of all urban vehicle trips and produce large impacts in key areas, such as congestion, emissions, road wear, and industrial area traffic. A system for modeling such movements was developed for Calgary, Alberta, Canada. It is a novel application of an agent-based microsimulation framework that uses a tour-based approach and emphasizes important elements of urban commercial movement, including the role of service delivery, light commercial vehicles, and trip chaining. The microsimulation uses Monte Carlo techniques to assign tour purpose, vehicle type, next-stop purpose, next-stop location, and next-stop duration. Tours are “grown” with a return-to-establishment alternative within the next-stop purpose allocation, which is consistent with the nature of tour making in urban commercial movements. The Monte Carlo probabilities are established with the use of a series of logit models, with coefficients estimated on the basis of observed behavior of different commercial movement segments. The estimation results in themselves provide insights into the revealed behavior that have not been available previously.

scholarly journals Agent-based modelling and parameter sensitivity analysis with a finite-element method for skin contraction

2020 ◽  
Vol 19 (6) ◽  
pp. 2525-2551
Author(s):  
Qiyao Peng ◽  
Fred Vermolen
Keyword(s):  
Wound Healing ◽  
Density Ratio ◽  
Strong Positive Correlation ◽  
Strong Negative Correlation ◽  
Wound Area ◽  
Agent Based ◽  
Signalling Molecules ◽  
Biological Phenomena ◽  
Collagen Density ◽  
Parameter Values

Abstract In this paper, we extend the model of wound healing by Boon et al. (J Biomech 49(8):1388–1401, 2016). In addition to explaining the model explicitly regarding every component, namely cells, signalling molecules and tissue bundles, we categorized fibroblasts as regular fibroblasts and myofibroblasts. We do so since it is widely documented that myofibroblasts play a significant role during wound healing and skin contraction and that they are the main phenotype of cells that is responsible for the permanent deformations. Furthermore, we carried out some sensitivity tests of the model by modifying certain parameter values, and we observe that the model shows some consistency with several biological phenomena. Using Monte Carlo simulations, we found that there is a significant strong positive correlation between the final wound area and the minimal wound area. The high correlation between the wound area after 4 days and the final/minimal wound area makes it possible for physicians to predict the most probable time evolution of the wound of the patient. However, the collagen density ratio at the time when the wound area reaches its equilibrium and minimum, cannot indicate the degree of wound contractions, whereas at the 4th day post-wounding, when the collagen is accumulating from null, there is a strong negative correlation between the area and the collagen density ratio. Further, under the circumstances that we modelled, the probability that patients will end up with 5% contraction is about 0.627.

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