Tuesday, June 08, 2010

Crowd Size at 6/6/10 Demo against 9/11 Mega-Mosque

One can estimate the crowd size from this video of the June 6 protest.

As the camera pans from right to left and left to right, one can count 14 metal gates lined up from one end of the pen to the other end. Those 14 gates form the side of the whole pen closest to the video camera.

The crowd leans against 10 of those 14 gates, while 4 of them, the 4 gates farthest to the left, are in the speakers' area and are more or less unoccupied.

The shape of the crowd narrows toward the front of the demo, where the speakers are.

First I'll estimate that along the side of each of the ten gates where there are demonstrators, one finds an average of about 4.5 demonstrators. You can sort of count them, though the video is not very clear.
10 gates x 4.5 people per gate = 45 people from one end of the demo to the other end where the speakers area begins.

Then, assuming that the crowd was approximately square (admittedly a big assumption), one gets 45 x 45 = 2025 demonstrators.

A further consideration might increase that number: it seems that leaning on the gates causes people to spread out a bit: unless I'm mistaken, the crowd is denser as soon as one looks at people not leaning on the gates.

Thus the real multipliers might not be 45 x 45, but, say 50 x 50 = 2500 demonstrators.

Then we must add to that the front of the crowd near the speakers and their staff, in the area of the front four gates. Also we must add some other people who were crowding up across a street that was visible at the beginning of the video.

Thus if we calculate all of those at the narrowing front of the demo plus all of those on the street at the back of the demo as an additional 300 people, we get a total of about 2800.

So media reports of 1000 certainly seem to be low-ball reports.

If anyone can find errors in my guesstimates here, or make them more precise, please do. I counted 14 gates as the camera pans from right to left and left to right, but the overall count of people depends also on something I could not count, namely the depth of the demo as one looks toward the horizon. Was the demo space as deep as it was long (14 gates long)? Was it deeper still? Or less deep? It looks about square, or perhaps less deep than long. In my guesstimate of the crowd count, I've assumed the crowd was the equivalent of ten gates deep. But if the demo was, for example, ten people (two gates) deeper than I've assumed, that added depth would increase by about 500 my guess at the total crowd count.

Another consideration is how much turnover there was during the course of the demo, i.e., people leaving and people arriving. For example if 3000 people come and stay an average of an hour, and another 3000 mingle in later as the first 3000 mingle out, the size of the crowd the whole time might stay constant at 3000, yet the total number of people coming and going to the event would be 6000.

How many hours did this demo last? Perhaps there was not much turnover, but it might be one factor in a calculation.

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