Tuesday, February 01, 2011

Cairo Crowd Estimates

Let me first say that the real events in Egypt are much more interesting and important than this post and I support everyone on the streets there, but my thingy for numbers made me investigate the crowd estimates a bit more.

Al Jazeera is reporting up to 2 million people have gathered in Cairo's Tahrir square, some reporters even get extremely excited and say at least 2 million people have gathered. 2 million people is 40x the Lowlands festival!

This image shows one of the edges of the crowd, to get an idea of where the crowd ends,

Here is a visual overview of crowd densities. A density of 1-5 per square meter is possible, although 5 is extremely dense. Let's take 4 per square meter, which is already very high,

Now lets look at an area of 100,000 square meter in Cairo,
About 400,000 people could stand on this area, although 200,000-300,000 is probably more realistic if there are no naked women handed out for free in the centre. Also keep in mind that the full Washington Mall is 15x larger, 1.5 million square meter.

Even if we take the high estimate of 4 people per square meter, an area 5 times larger than the one shown above is required for 2 million people.

Too bad there are no good overview images (RC helicopters, where are you?!) so I can't make any serious estimate, but I would be surprised if "even" 1 million people are in and around the square. My guesstimate would be 100,000-400,000.

Still a lot of people, especially for Egypt, and I hope enough.


cybrbeast said...

Nice analysis. I wonder why Al Jazeera overestimated it. Is it just lack of expertise and copying the name "march of a million people", or are they biased?

NPR states in a good article: "The crowd — estimated to be anywhere from 250,000 to 2 million people — was by far the largest rally during a week of demonstrations and unrest. "

annom said...

Al Jazeera is biased and their lack of expertise allows for bias.

cybrbeast said...

Do you see a systematic bias or just in this case?

Usually I'm under the impression that their reporting is quite neutral and not as shallow as many other news sources. Also a lot of former BBC employees work for Al Jazeera.

annom said...

Well, their journalists are, not surprisingly, in the anti-M camp. But many, especially those in the streets, don't try to hide it or can't in their excitement.

I believe they have genuine motives and don't consciously try to manipulate the news, but they are biased. It has a certain romantic taste to it though :)

pimp-a-lot bear said...

Nice post, and yes, the numbers estimated by AL-jazeera are clearly too high.

Al-jazeera is definitely biased, but it's not pro-Arab, anti-Semite, anti-American or whatever you want to call it. But they do tend to ally with those who are powerless and voice their concerns, and they often exaggerate these concerns.

GKStill said...

Nearly all crowd estimates by the media and/or authorities and gross OVER estimate.

Nice use of the calculations..