Crowd counting
From Wikipedia, the free encyclopedia
Crowd counting techniques are used to count or estimate the number of people in a crowd. At ticketed events, turnstiles are often used to precisely count the number of people entering a venue. At unticketed events, especially events that take place in the streets or a park rather than an enclosed venue, crowd counting is more difficult and less precise. For many events, especially political rallies or protests, the number of people in a crowd carries political significance and counts are controversial. For instance, the global protests against the Iraq war saw many protests at which widely differing counts were offered by organizers on one side and the police on the other. Another memorable incident occurred when Louis Farrakhan threatened to sue the Washington, D.C. Park Police for announcing that only 400,000 people attended the 1995 Million Man March he organized.
The most common technique for counting crowds at protests and rallies is dividing the area occupied by a crowd into sections, determining an average number of people in each section, and multiplying by the number of sections occupied.