Lutz Bornmann and Loet Leydesdorff created interactive world maps which denote the locations from which scientific papers were authored. Green dots represent higher quality research and red dots signify lower quality research. There are three maps, one each for physics, chemistry, and psychology:
The idea is simple enough - scientific papers cite other scientific papers and it is usually held that the more a paper is cited the more important it is. So taking the data from the Web-of-Science database the researchers simply counted how many papers originated from each city and plotted a circle with a radius proportional to the number of papers on Google Maps.
They then looked at the number of papers that you would expect to be in the top 10% most cited papers from each city, i.e. 10% of the papers compared to the number that were actually in the top 10%. The difference indicates how successful the city is in producing important papers and not just their volume. They plotted the circles in red for lower performing cities and green for higher performing cities.
Pictured above is a selection from the physics map.
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