Here's a beautiful aerial of Sunday's Juanes concert from Juventud Rebelde. Photo credit: Geovani Fernández
Juventud Rebelde said more than a million people packed Revolution Square. Spanish singer Miguel Bose was more precise, announcing that the crowd size was 1.15 million, the Associated Press reported.
Is that possible? How many people does Revolution Square hold? And how do you figure out crowd size anyway?
There are three key questions, according to Clark McPhail, a sociology professor at the University of Illinois:
* What is the square footage of the public space?
* How much of that space is occupied?
* How tightly are people packed into the space?
So let's start with the size of Revolution Square. Wikipedia says it measures 72,000 square meters. That's 775,001 square feet, according to an online converter at Easysurf.
Now let's figure out how many people can fit in each square foot. Evidently, this number can vary quite a bit.
Let's assume there was a very dense crowd at the Juanes concert, say, one person for every 1.35 square feet.
That was the figure used in one calculation of the crowd that saw Barack Obama's inauguration. So if you divide 775,001 square feet by 1.35, that's 574,075 people.
Figure there were another 75,000 people on side streets near Revolution Square. That's 649,075. But Miguel Bose announced a crowd size of 1.15 million.
So where are the other 500,925 people? Is my calculation way off? I don't pretend to be an expert on crowd counts, but the numbers don't add up.
Can you fit more than one person into 1.35 square feet? Is Revolution Square actually bigger than 775,001 square feet? Or did organizers exaggerate the number of people at the Juanes concert?
I don't know. I wasn't there. And neither was Clark McPhail. But in an interview published before Barack Obama's inauguration, the University of Illinois professor said crowd counts are usually “guesstimates,” and often hugely inflated.
McPhail has been studying crowd behavior and crowds for decades and is the author of “The Myth of the Madding Crowd.”
He says the ego of organizers, along with errors in calculation, often lead to inflated crowd counts.
I'll bet there is computer software out there that can take a digital image and estimate how many people are in the crowd. That might answer some of these questions.