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Article ; Online: A simulated 'sandbox' for exploring the modifiable areal unit problem in aggregation and disaggregation.

Nieves, Jeremiah J / Gaughan, Andrea E / Stevens, Forrest R / Yetman, Greg / Gros, Andreas

2024 Volume 11, Issue 1, Page(s) 239

Abstract: We present a spatial testbed of simulated boundary data based on a set of very high-resolution census-based areal units surrounding Guadalajara, Mexico. From these input areal units, we simulated 10 levels of spatial resolutions, ranging from levels with ...

Abstract	We present a spatial testbed of simulated boundary data based on a set of very high-resolution census-based areal units surrounding Guadalajara, Mexico. From these input areal units, we simulated 10 levels of spatial resolutions, ranging from levels with 5,515-52,388 units and 100 simulated zonal configurations for each level - totalling 1,000 simulated sets of areal units. These data facilitate interrogating various realizations of the data and the effects of the spatial coarseness and zonal configurations, the Modifiable Areal Unit Problem (MAUP), on applications such as model training, model prediction, disaggregation, and aggregation processes. Further, these data can facilitate the production of spatially explicit, non-parametric estimates of confidence intervals via bootstrapping. We provide a pre-processed version of these 1,000 simulated sets of areal units, meta- and summary data to assist in their use, and a code notebook with the means to alter and/or reproduce these data.
Language	English
Publishing date	2024-02-24
Publishing country	England
Document type	Dataset ; Journal Article
ZDB-ID	2775191-0
ISSN	2052-4463 ; 2052-4463
ISSN (online)	2052-4463
ISSN	2052-4463
DOI	10.1038/s41597-024-03061-1
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Book ; Online ; Thesis: Interactions in the evolution of dispersal distance and emigration probability

Gros, Andreas [Verfasser]

2008

Author's details	vorgelegt von Andreas Gros
Keywords	Biowissenschaften, Biologie ; Life Science, Biology
Subject code	sg570
Language	English
Document type	Book ; Online ; Thesis
Database	Digital theses on the web

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Article ; Online: The ability of individuals to assess population density influences the evolution of emigration propensity and dispersal distance.

Poethke, Hans Joachim / Gros, Andreas / Hovestadt, Thomas

Journal of theoretical biology

2011 Volume 282, Issue 1, Page(s) 93–99

Abstract: We analyze the simultaneous evolution of emigration and settlement decisions for actively dispersing species differing in their ability to assess population density. Using an individual-based model we simulate dispersal as a multi-step (patch to patch) ... ...

Abstract	We analyze the simultaneous evolution of emigration and settlement decisions for actively dispersing species differing in their ability to assess population density. Using an individual-based model we simulate dispersal as a multi-step (patch to patch) movement in a world consisting of habitat patches surrounded by a hostile matrix. Each such step is associated with the same mortality risk. Our simulations show that individuals following an informed strategy, where emigration (and settlement) probability depends on local population density, evolve a lower (natal) emigration propensity but disperse over significantly larger distances - i.e. postpone settlement longer - than individuals performing density-independent emigration. This holds especially when variation in environmental conditions is spatially correlated. Both effects can be traced to the informed individuals' ability to better exploit existing heterogeneity in reproductive chances. Yet, already moderate distance-dependent dispersal costs prevent the evolution of multi-step (long-distance) dispersal, irrespective of the dispersal strategy.
MeSH term(s)	Biological Evolution ; Humans ; Models, Theoretical ; Population Density
Language	English
Publishing date	2011-08-07
Publishing country	England
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	2972-5
ISSN	1095-8541 ; 0022-5193
ISSN (online)	1095-8541
ISSN	0022-5193
DOI	10.1016/j.jtbi.2011.05.012
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Article: The ability of individuals to assess population density influences the evolution of emigration propensity and dispersal distance

Poethke, Hans Joachim / Gros, Andreas / Hovestadt, Thomas

Journal of theoretical biology. 2011 Aug. 7, v. 282, no. 1

2011

Abstract	We analyze the simultaneous evolution of emigration and settlement decisions for actively dispersing species differing in their ability to assess population density. Using an individual-based model we simulate dispersal as a multi-step (patch to patch) movement in a world consisting of habitat patches surrounded by a hostile matrix. Each such step is associated with the same mortality risk. Our simulations show that individuals following an informed strategy, where emigration (and settlement) probability depends on local population density, evolve a lower (natal) emigration propensity but disperse over significantly larger distances – i.e. postpone settlement longer – than individuals performing density-independent emigration. This holds especially when variation in environmental conditions is spatially correlated. Both effects can be traced to the informed individuals' ability to better exploit existing heterogeneity in reproductive chances. Yet, already moderate distance-dependent dispersal costs prevent the evolution of multi-step (long-distance) dispersal, irrespective of the dispersal strategy.
Keywords	environmental factors ; evolution ; habitats ; models ; mortality ; population density ; risk
Language	English
Dates of publication	2011-0807
Size	p. 93-99.
Publishing place	Elsevier Ltd
Document type	Article
ZDB-ID	2972-5
ISSN	1095-8541 ; 0022-5193
ISSN (online)	1095-8541
ISSN	0022-5193
DOI	10.1016/j.jtbi.2011.05.012
Database	NAL-Catalogue (AGRICOLA)

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Article ; Online: Sex-specific spatio-temporal variability in reproductive success promotes the evolution of sex-biased dispersal.

Gros, Andreas / Poethke, Hans Joachim / Hovestadt, Thomas

Theoretical population biology

2009 Volume 76, Issue 1, Page(s) 13–18

Abstract: Inbreeding depression, asymmetries in costs or benefits of dispersal, and the mating system have been identified as potential factors underlying the evolution of sex-biased dispersal. We use individual-based simulations to explore how the mating system ... ...

Abstract	Inbreeding depression, asymmetries in costs or benefits of dispersal, and the mating system have been identified as potential factors underlying the evolution of sex-biased dispersal. We use individual-based simulations to explore how the mating system and demographic stochasticity influence the evolution of sex-specific dispersal in a metapopulation with females competing over breeding sites, and males over mating opportunities. Comparison of simulation results for random mating with those for a harem system (locally, a single male sires all offspring) reveal that even extreme variance in local male reproductive success (extreme male competition) does not induce male-biased dispersal. The latter evolves if the between-patch variance in reproductive success is larger for males than females. This can emerge due to demographic stochasticity if the habitat patches are small. More generally, members of a group of individuals experiencing higher spatio-temporal variance in fitness expectations may evolve to disperse with greater probability than others.
MeSH term(s)	Animals ; Biological Evolution ; Competitive Behavior/physiology ; Computer Simulation ; Demography ; Female ; Inbreeding ; Male ; Mammals/physiology ; Models, Theoretical ; Population Dynamics ; Probability ; Reproduction/physiology ; Sex Characteristics ; Sexual Behavior, Animal ; Stochastic Processes
Language	English
Publishing date	2009-08
Publishing country	United States
Document type	Journal Article ; Research Support, Non-U.S. Gov't
ZDB-ID	3948-2
ISSN	1096-0325 ; 0040-5809
ISSN (online)	1096-0325
ISSN	0040-5809
DOI	10.1016/j.tpb.2009.03.002
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Article: Modeling policy and agricultural decisions in Afghanistan

Widener, Michael J / Bar-Yam, Yavni / Gros, Andreas / Metcalf, Sara S / Bar-Yam, Yaneer

GeoJournal. 2013 Aug., v. 78, no. 4

2013

Abstract: Afghanistan is responsible for the majority of the world’s supply of poppy crops, which are often used to produce illegal narcotics like heroin. This paper presents an agent-based model that simulates policy scenarios to characterize how the production ... ...

Abstract	Afghanistan is responsible for the majority of the world’s supply of poppy crops, which are often used to produce illegal narcotics like heroin. This paper presents an agent-based model that simulates policy scenarios to characterize how the production of poppy can be dampened and replaced with licit crops over time. The model is initialized with spatial data, including transportation network and satellite-derived land use data. Parameters representing national subsidies, insurgent influence, and trafficking blockades are varied to represent different conditions that might encourage or discourage poppy agriculture. Our model shows that boundary-level interventions, such as targeted trafficking blockades at border locations, are critical in reducing the attractiveness of growing this illicit crop. The principle of least effort implies that interventions decrease to a minimal non-regressive point, leading to the prediction that increases in insurgency or other changes are likely to lead to worsening conditions, and improvements require substantial jumps in intervention resources.
Keywords	agricultural policy ; crops ; land use ; models ; narcotics ; prediction ; spatial data ; subsidies ; transportation ; Afghanistan
Language	English
Dates of publication	2013-08
Size	p. 591-599.
Publishing place	Springer-Verlag
Document type	Article
ZDB-ID	715360-0
ISSN	1572-9893 ; 0343-2521
ISSN (online)	1572-9893
ISSN	0343-2521
DOI	10.1007/s10708-012-9453-y
Database	NAL-Catalogue (AGRICOLA)

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Book ; Online: Eco-Evolutionary Feedback in Host--Pathogen Spatial Dynamics

Stacey, Blake C. / Gros, Andreas / Bar-Yam, Yaneer

2011

Abstract: Spatial extent is a complicating factor in mathematical biology. The possibility that an action at point A cannot immediately affect what happens at point B creates the opportunity for spatial nonuniformity. This nonuniformity must change our ... ...

Abstract	Spatial extent is a complicating factor in mathematical biology. The possibility that an action at point A cannot immediately affect what happens at point B creates the opportunity for spatial nonuniformity. This nonuniformity must change our understanding of evolutionary dynamics, as the same organism in different places can have different expected evolutionary outcomes. Since organism origins and fates are both determined locally, we must consider heterogeneity explicitly to determine its effects. We use simulations of spatially extended host--pathogen and predator--prey ecosystems to reveal the limitations of standard mathematical treatments of spatial heterogeneity. Our model ecosystem generates heterogeneity dynamically; an adaptive network of hosts on which pathogens are transmitted arises as an emergent phenomenon. The structure and dynamics of this network differ in significant ways from those of related models studied in the adaptive-network field. We use a new technique, organism swapping, to test the efficacy of both simple approximations and more elaborate moment-closure methods, and a new measure to reveal the timescale dependence of invasive-strain behavior. Our results demonstrate the failure not only of the most straightforward ("mean field") approximation, which smooths over heterogeneity entirely, but also of the standard correction ("pair approximation") to the mean field treatment. In spatial contexts, invasive pathogen varieties can prosper initially but perish in the medium term, implying that the concepts of reproductive fitness and the Evolutionary Stable Strategy have to be modified for such systems. Comment: 37 pages, 6 figures; also presented in the Adaptive Networks session of ICCS 2011. Revision: new title, crossover times examined in more detail, order of presentation changed, bibliography updated
Keywords	Nonlinear Sciences - Cellular Automata and Lattice Gases ; Nonlinear Sciences - Adaptation and Self-Organizing Systems ; Quantitative Biology - Populations and Evolution
Subject code	501
Publishing date	2011-10-17
Publishing country	us
Document type	Book ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Book ; Online: Sentiment in New York City

Bertrand, Karla Z. / Bialik, Maya / Virdee, Kawandeep / Gros, Andreas / Bar-Yam, Yaneer

A High Resolution Spatial and Temporal View

2013

Abstract: Measuring public sentiment is a key task for researchers and policymakers alike. The explosion of available social media data allows for a more time-sensitive and geographically specific analysis than ever before. In this paper we analyze data from the ... ...

Abstract	Measuring public sentiment is a key task for researchers and policymakers alike. The explosion of available social media data allows for a more time-sensitive and geographically specific analysis than ever before. In this paper we analyze data from the micro-blogging site Twitter and generate a sentiment map of New York City. We develop a classifier specifically tuned for 140-character Twitter messages, or tweets, using key words, phrases and emoticons to determine the mood of each tweet. This method, combined with geotagging provided by users, enables us to gauge public sentiment on extremely fine-grained spatial and temporal scales. We find that public mood is generally highest in public parks and lowest at transportation hubs, and locate other areas of strong sentiment such as cemeteries, medical centers, a jail, and a sewage facility. Sentiment progressively improves with proximity to Times Square. Periodic patterns of sentiment fluctuate on both a daily and a weekly scale: more positive tweets are posted on weekends than on weekdays, with a daily peak in sentiment around midnight and a nadir between 9:00 a.m. and noon. Comment: 12 pages, 5 figures
Keywords	Physics - Physics and Society ; Computer Science - Computation and Language ; Computer Science - Computers and Society
Subject code	910
Publishing date	2013-08-22
Publishing country	us
Document type	Book ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Good fences: the importance of setting boundaries for peaceful coexistence.

Rutherford, Alex / Harmon, Dion / Werfel, Justin / Gard-Murray, Alexander S / Bar-Yam, Shlomiya / Gros, Andreas / Xulvi-Brunet, Ramon / Bar-Yam, Yaneer

PloS one

2014 Volume 9, Issue 5, Page(s) e95660

Abstract: We consider the conditions of peace and violence among ethnic groups, testing a theory designed to predict the locations of violence and interventions that can promote peace. Characterizing the model's success in predicting peace requires examples where ... ...

Abstract	We consider the conditions of peace and violence among ethnic groups, testing a theory designed to predict the locations of violence and interventions that can promote peace. Characterizing the model's success in predicting peace requires examples where peace prevails despite diversity. Switzerland is recognized as a country of peace, stability and prosperity. This is surprising because of its linguistic and religious diversity that in other parts of the world lead to conflict and violence. Here we analyze how peaceful stability is maintained. Our analysis shows that peace does not depend on integrated coexistence, but rather on well defined topographical and political boundaries separating groups, allowing for partial autonomy within a single country. In Switzerland, mountains and lakes are an important part of the boundaries between sharply defined linguistic areas. Political canton and circle (sub-canton) boundaries often separate religious groups. Where such boundaries do not appear to be sufficient, we find that specific aspects of the population distribution guarantee either sufficient separation or sufficient mixing to inhibit intergroup violence according to the quantitative theory of conflict. In exactly one region, a porous mountain range does not adequately separate linguistic groups and that region has experienced significant violent conflict, leading to the recent creation of the canton of Jura. Our analysis supports the hypothesis that violence between groups can be inhibited by physical and political boundaries. A similar analysis of the area of the former Yugoslavia shows that during widespread ethnic violence existing political boundaries did not coincide with the boundaries of distinct groups, but peace prevailed in specific areas where they did coincide. The success of peace in Switzerland may serve as a model to resolve conflict in other ethnically diverse countries and regions of the world.
MeSH term(s)	Conflict, Psychological ; Ethnic Groups ; Humans ; Language ; Politics ; Social Conditions ; Social Control, Informal ; Social Environment ; Switzerland ; Yugoslavia
Language	English
Publishing date	2014-05-21
Publishing country	United States
Document type	Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
ISSN	1932-6203
ISSN (online)	1932-6203
DOI	10.1371/journal.pone.0095660
Database	MEDical Literature Analysis and Retrieval System OnLINE

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Book ; Online: Good Fences

Rutherford, Alex / Harmon, Dion / Werfel, Justin / Bar-Yam, Shlomiya / Gard-Murray, Alexander / Gros, Andreas / Bar-Yam, Yaneer

The Importance of Setting Boundaries for Peaceful Coexistence

2011

Abstract	We consider the conditions of peace and violence among ethnic groups, testing a theory designed to predict the locations of violence and interventions that can promote peace. Characterizing the model's success in predicting peace requires examples where peace prevails despite diversity. Switzerland is recognized as a country of peace, stability and prosperity. This is surprising because of its linguistic and religious diversity that in other parts of the world lead to conflict and violence. Here we analyze how peaceful stability is maintained. Our analysis shows that peace does not depend on integrated coexistence, but rather on well defined topographical and political boundaries separating groups. Mountains and lakes are an important part of the boundaries between sharply defined linguistic areas. Political canton and circle (sub-canton) boundaries often separate religious groups. Where such boundaries do not appear to be sufficient, we find that specific aspects of the population distribution either guarantee sufficient separation or sufficient mixing to inhibit intergroup violence according to the quantitative theory of conflict. In exactly one region, a porous mountain range does not adequately separate linguistic groups and violent conflict has led to the recent creation of the canton of Jura. Our analysis supports the hypothesis that violence between groups can be inhibited by physical and political boundaries. A similar analysis of the area of the former Yugoslavia shows that during widespread ethnic violence existing political boundaries did not coincide with the boundaries of distinct groups, but peace prevailed in specific areas where they did coincide. The success of peace in Switzerland may serve as a model to resolve conflict in other ethnically diverse countries and regions of the world. Comment: paper pages 1-14, 4 figures; appendices pages 15-43, 20 figures
Keywords	Physics - Physics and Society ; Computer Science - Social and Information Networks
Subject code	390
Publishing date	2011-10-06
Publishing country	us
Document type	Book ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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