Every time I read about a big political rally, one thing I notice is that there are always a variety of different estimates of the size of the event from various news outlets and rally organizers. I was curious as to what methods are used to estimate the crowd sizes. Aerial photography? Measuring how much space the rally occupies? Timing the marches? I’ve been wondering about this for a while and was hoping someone here could give me an idea. Thanks.
I only know of one method. It’s supposed to be pretty good. You’ll need to be able to view from above somewhat. Put some sort of box in your field of vision and count the number of people in the box. It could be making a box with your fingers. Then count the number of boxes in the space. Multiply the two figures for your estimate. I 'spose for more accuracy you could take a number of box counts and average that. I don’t know if that’s how they do it.
I think that generally, when you read numbers from various sources–usually the organizers and the police–both sides are pretty much picking numbers from their buttocks, and the real number is somewhere in between. Most likely it’s closer to the police’s count, since they have experience with that sort of thing and they have nothing to gain from over/underestimating.
I asked myself this question within the past couple of weeks and surfed the web.
Points to remember:
- The police have no special training or skills in crowd size measurement.
- The media knows this.
- But the media wants a number. Immediately. Never mind the quality.
- So bogus crowd size estimates will continue to be kicked around with little to back them up.
This site ( http://www.bu.edu/remotesensing/Research/MMM/MMMnew.html ) shows a study by Dr. Farouk EL-Baz, director of the Center for Remote Sensing at Boston University, which used a number of photos of the million man march to estimate that event’s size. Their estimate (650,000 - 1.1 million, midpoint 870,000) reflected the work of 10 research associates during a single evening. It was higher than the Park Service’s estimate of 400,000 and lower than the Nation of Islam’s take at 1.5 to 2 million. Later work narrowed the range of the estimate a little.
I remember reading something how the maximum number of people that could possibily have attended an event is usually calculated at 4 people per square meter (this helps eliminates some groups super high claims.)
it’s simple.
Count the legs and divide by 2.
what about pirate rallies?
When I go to large rallies (in my role as a news producer) I tend to come up with an estimate based on a partial count: Tally up the people in one line, then count the number of lines of marchers, fer instance.
Everyone from other media types to cops to the rally holders looks at me like a freak when I do this.
Count either the parrots or steering wheels.
There are two methods used by the news media for crowd estimation. One uses statistics and the other doesn’t. They are called SWAG and WAG respectively.
There is a third method used only by event organizers called “WT” which stands for wishful thinking and usually about three times the WAG number.
[Dougal McGuire (From Father Ted)]
“Ted, I’m no good at estimating crowds, but I’d say there’s at least 17 million of them out there…”
[/ Dougal]
The National Park Service used to do “official crowd estimates”. They got so much flak after the Million Man March for supposedly undercounting (flowbark’s cite being the major evidence) that Congress had them stop doing them entirely.