10:04 04 June 2015
Researchers from Warwick University conducted a study concluding that geographical data from mobile phones and Twitter can be used to estimate the size of a large crowd. They conducted the study in a football stadium and an airport analyzing geo-tagged tweets. The team that it could enable measurement of events such as protests.
"These are the numbers - the calibration examples - that we can draw on," said co-author Dr Tobias Preis. "Obviously it would be even better if there were training examples in other countries, other environments, other time periods. Human behaviour is not constant around the globe.
"But it's a very, very good base to build on, to provide initial estimates."
Federico Botta, the PhD student who led the analysis, said: "This is very quick. It does not rely on human judgement, it only relies on having the data related to mobile phones, or Twitter activity."
When it comes to error margin, Mr Botta explained: "Our mean absolute percentage error is about 13%. That means that our estimate and the actual number of people differ in absolute value by roughly 13%."