what ’ s happening .”
Understanding the accuracy of such information is also important , said Tsou , whose recent study explored the interaction between cyberspace message activity ( measured by keyword-specific tweets ) and real-world occurrences of influenza and pertussis . Tweets were collected within a 17-mile radius of 11 U . S . cities chosen on the basis of population and the availability of disease data . Tweets were then aggregated by week and compared to weekly influenza-like illness and pertussis incidence . The correlation coefficients between tweets or subgroups of tweets and disease occurrence were then calculated and trends were presented graphically .
“ The correlation between the weekly flu tweets versus the national flu data was almost 86 percent ,” said Tsou . “ It was a very high correlation . Even more
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