image: Using an enormous collection of Twitter messages from across the globe, the researchers measured people's positive and negative affect, or mood, worldwide. This map shows the average level of these positive feelings in each country. This image relates to an article that appeared in the Sept. 30, 2011, issue of Science, published by AAAS. The study, by Dr. S.A. Golder of Cornell University, in Ithaca, N.Y., and colleagues was titled, "Diurnal and Seasonal Mood Vary with Work, Sleep, and Daylength Across Diverse Cultures." view more
Credit: Image © <i>Science</i>/AAAS