Editing Swarm behaviour (section)

==People==
[[File:Police protect Nick Altrock from adoring crowd, 1906 World Series.jpg|thumb|right|Police protect [[Nick Altrock]] from an adoring crowd during [[baseball]]'s [[1906 World Series]]]]
{{External media
|float=right
|width=228px
|image1=[http://hal.elte.hu/~vicsek/MW.html Mexican wave simulation]<ref>{{cite journal |vauthors= Farkas I, Helbing D, Vicsek T |year= 2002 |title= Mexican waves in an excitable medium |url= http://angel.elte.hu/~vicsek/pdf/MexWave.pdf |journal= Nature |volume= 419 |issue= 6903 |pages= 131–132 |doi= 10.1038/419131a |pmid= 12226653 |arxiv= cond-mat/0210073 |bibcode= 2002Natur.419..131F |s2cid= 4309609 |url-status= dead |archive-url= https://web.archive.org/web/20070710054159/http://angel.elte.hu/~vicsek/pdf/MexWave.pdf |archive-date= 2007-07-10}}</ref>
|image2=[http://hal.elte.hu/~vicsek/RA.html Rhythmic applause simulation]<ref>{{cite journal |vauthors= Neda Z, Ravasz E, Brechet Y, Vicsek T, Barabasi AL |year= 2002 |title= Physics of Rhythmic Applause |url= http://angel.elte.hu/~vicsek/pdf/longpaper.pdf |archive-url= https://web.archive.org/web/20110611091441/http://angel.elte.hu/~vicsek/pdf/longpaper.pdf |url-status= dead |archive-date= 2011-06-11 |journal= Physical Review E |volume= 61 |issue= 6 |pages= 6987–6992 |doi= 10.1103/physreve.61.6987 |pmid= 11088392 |arxiv= cond-mat/0006423 |bibcode= 2000PhRvE..61.6987N|s2cid= 14135891 }}</ref>}}
{{See also|Crowd|Crowd simulation}}

A collection of people can also exhibit swarm behaviour, such as pedestrians<ref>{{cite journal |last1= Helbing |first1= D |last2= Keltsch |first2= J |last3= Molnar |first3= P |year= 1997 |title= Modelling the evolution of human trail systems |journal= Nature |volume= 388 |issue= 6637 |pages= 47–50 |doi=10.1038/40353 |pmid=9214501|arxiv=cond-mat/9805158 |bibcode= 1997Natur.388...47H|s2cid= 4364517 }}</ref> or soldiers swarming the parapets{{dubious|date=May 2019}}. In Cologne, Germany, two biologists from the University of Leeds demonstrated flock like behaviour in humans. The group of people exhibited similar behavioural pattern to a flock, where if five percent of the flock changed direction the others would follow. If one person was designated as a predator and everyone else was to avoid him, the flock behaved very much like a school of fish.<ref>"http://psychcentral.com/news/2008/02/15/herd-mentality-explained/1922.html {{Webarchive|url=https://web.archive.org/web/20141129010932/http://psychcentral.com/news/2008/02/15/herd-mentality-explained/1922.html |date=29 November 2014 }}". Retrieved on October 31st 2008.</ref><ref>{{cite web |url=http://www.thenational.ae/news/uae-news/science/danger-in-numbers-during-haj?pageCount=2|title=Danger in numbers during Haj|date=6 September 2009|publisher=The National}}</ref> Understanding how humans interact in crowds is important if crowd management is to effectively avoid casualties at football grounds, music concerts and subway stations.<ref>{{cite book |vauthors= Couzin ID, Krause J |year= 2003 |title= Self-organization and collective behavior in vertebrates |url= http://webscript.princeton.edu/~icouzin/website/wp-content/uploads/2010/07/CouzinKrause2003.pdf |volume= 32 |pages= 1–75 |doi= 10.1016/S0065-3454(03)01001-5 |series= Advances in the Study of Behavior |isbn= 978-0-12-004532-7 |access-date= 14 April 2011 |archive-date= 13 March 2012 |archive-url= https://web.archive.org/web/20120313132355/http://webscript.princeton.edu/~icouzin/website/wp-content/uploads/2010/07/CouzinKrause2003.pdf |url-status= dead }}</ref>

The mathematical modelling of [[flocking behaviour]] is a common technology, and has found uses in animation. Flocking simulations have been used in many films<ref>{{cite thesis |last=Gabbai |first=J.M.E. |title=Complexity and the Aerospace Industry: Understanding Emergence by Relating Structure to Performance using Multi-Agent Systems |year=2005 |publisher=University of Manchester Doctoral Thesis |place=Manchester |url=http://www.gabbai.com/academic/complexity-and-the-aerospace-industry-understanding-emergence-by-relating-structure-to-performance-using-multi-agent-systems/ |access-date=11 July 2009 |archive-date=19 December 2014 |archive-url=https://web.archive.org/web/20141219110658/http://gabbai.com/academic/complexity-and-the-aerospace-industry-understanding-emergence-by-relating-structure-to-performance-using-multi-agent-systems |url-status=dead }}</ref> to [[crowd simulation|generate crowds]] which move realistically. Tim Burton's ''[[Batman Returns]]'' was the first movie to make use of swarm technology for rendering, realistically depicting the movements of a group of bats using the [[boids]] system. [[The Lord of the Rings (film series)|''The Lord of the Rings'' film trilogy]] made use of similar technology, known as [[Massive (software)|Massive]], during battle scenes. Swarm technology is particularly attractive because it is cheap, robust, and simple.

An ant-based computer simulation using only six interaction rules has also been used to evaluate aircraft boarding behaviour.<ref>Livermore R (2008) [http://computing-reports.open.ac.uk/2008/TR2008-25.pdf "A multi-agent system approach to a simulation study comparing the performance of aircraft boarding using pre-assigned seating and free-for-all strategies"] {{Webarchive|url=https://web.archive.org/web/20110813221456/http://computing-reports.open.ac.uk/2008/TR2008-25.pdf |date=13 August 2011 }} ''Open University'', Technical report No 2008/25.</ref> Airlines have also used ant-based routing in assigning aircraft arrivals to airport gates. An airline system developed by [[Douglas A. Lawson]] uses swarm theory, or [[swarm intelligence]]—the idea that a colony of ants works better than one alone. Each pilot acts like an ant searching for the best airport gate. "The pilot learns from his experience what's the best for him, and it turns out that that's the best solution for the airline," Lawson explains. As a result, the "colony" of pilots always go to gates they can arrive and depart quickly. The program can even alert a pilot of plane back-ups before they happen. "We can anticipate that it's going to happen, so we'll have a gate available," says Lawson.<ref>[https://www.sciencedaily.com/videos/2008/0406-planes_trains_and_ant_hills.htm "Planes, Trains and Ant Hills: Computer scientists simulate activity of ants to reduce airline delays"] {{webarchive|url=https://web.archive.org/web/20101124132227/https://www.sciencedaily.com/videos/2008/0406-planes_trains_and_ant_hills.htm |date=2010-11-24}} ''Science Daily'', 1 April 2008.</ref>

Swarm behaviour occurs also in [[traffic flow]] dynamics, such as the [[traffic wave]]. [[Bidirectional traffic]] can be observed in [[ant]] trails.<ref name="Burd 2003">{{cite journal |title=Head-on encounter rates and walking speed of foragers in leaf-cutting ant traffic|journal=Insectes Sociaux|date=February 2003|first=Martin|last=Burd|author2=N. Aranwela |volume=50|issue=1|pages=3–8|doi= 10.1007/s000400300001|s2cid=23876486}}</ref><ref name='Ribeiro 2009'>{{cite journal |title=Ants can learn to forage on one-way trails|journal=PLOS ONE|editor1-first=Anna|date=2009-04-01|editor1-last=Dornhaus|first=Pedro|last=Ribeiro|author2=André Frazão Helene |author3=Gilberto Xavier |author4=Carlos Navas |author5=Fernando Leite Ribeiro |volume=4|issue=4|pages=e5024|doi= 10.1371/journal.pone.0005024|pmid=19337369|pmc=2659768 |bibcode= 2009PLoSO...4.5024R|doi-access=free}}</ref> In recent years this behaviour has been researched for insight into pedestrian and traffic models.<ref name='John 2008'>{{cite journal |title=Characteristics of ant-inspired traffic flow|journal=Swarm Intelligence|date=March 2008|first=Alexander|last=John|author2=Andreas Schadschneider |author3=Debashish Chowdhury |author4=Katsuhiro Nishinari |volume=2|issue=1|pages=25–41|doi= 10.1007/s11721-008-0010-8 |arxiv=0903.1434|s2cid=18350336}}</ref><ref>[http://www.economist.com/node/14020655 Are we nearly there yet? Motorists could learn a thing or two from ants] ''The Economist'', 10 July 2009.</ref> Simulations based on pedestrian models have also been applied to crowds which stampede because of panic.<ref>{{cite journal |last1=Helbing |first1=Dirk |last2=Farkas |first2=Illés |last3=Vicsek |first3=Tamás |title=Simulating dynamical features of escape panic |journal=Nature |volume=407 |issue=6803 |pages=487–490 |arxiv=cond-mat/0009448 |year=2000 |pmid=11028994 |doi=10.1038/35035023|bibcode= 2000Natur.407..487H|s2cid=310346 }}</ref>

[[Herd behaviour]] in [[marketing]] has been used to explain the dependencies of customers' mutual behaviour. ''[[The Economist]]'' reported a recent conference in [[Rome]] on the subject of the simulation of adaptive human behaviour.<ref>{{cite news |title= Swarming the shelves: How shops can exploit people's herd mentality to increase sales? |newspaper= The Economist |date= 2006-11-11 |page= 90}}</ref> It shared mechanisms to increase impulse buying and get people "to buy more by playing on the herd instinct." The basic idea is that people will buy more of products that are seen to be popular, and several feedback mechanisms to get product popularity information to consumers are mentioned, including [[smart card]] technology and the use of [[RFID|Radio Frequency Identification Tag]] technology. A "swarm-moves" model was introduced by a [[Florida Institute of Technology]] researcher, which is appealing to supermarkets because it can "increase sales without the need to give people discounts."

* {{cite journal |vauthors=Helbing D, Keltsch J, Molnar P |year= 1997 |title= Modelling the evolution of human trail systems |journal= Nature |volume= 388 |issue= 6637 |pages= 47–50 |arxiv= cond-mat/9805158 |doi= 10.1038/40353 |pmid= 9214501 |bibcode= 1997Natur.388...47H|s2cid= 4364517 }}
* {{cite journal |vauthors=Helbing D, Farkas I, Vicsek T |year= 2000 |title= Simulating dynamical features of escape panic |journal= Nature |volume= 407 |issue= 6803 |pages= 487–490 |doi= 10.1038/35035023 |pmid=11028994 |arxiv= cond-mat/0009448|bibcode= 2000Natur.407..487H|s2cid= 310346 }}
* {{cite journal |vauthors=Helbing D, Farkas IJ, Vicsek T |year= 2000 |title= Freezing by heating in a driven mesoscopic system |journal= Physical Review Letters |volume= 84 |issue= 6 |pages= 1240–1243 |doi= 10.1103/PhysRevLett.84.1240 |bibcode=2000PhRvL..84.1240H |arxiv= cond-mat/9904326 |pmid= 11017488|s2cid= 18649078 }}