Which cities in the world produced the most high-quality research in 2017? The Nature Index 2018 Science Cities, a supplement of the British scientific journal Nature, has the answer.

The journal sorted and ranked the top 200 science cities and metro areas (MA) by their 2017 fractional count (FC), which takes into account the share of authorship for each article.

The total FC available for any article is 1.0, which is shared among all authors under the assumption that each contributed equally to the article. For instance, an article with 5 authors means that each author receives an FC of 0.2.

The table accompanying the list also shows each city's total number of articles (AC) in 2017 regardless of the number of authors an article has, contribution to their country or region's total FC, and percentage of papers co-authored with researchers elsewhere.

Ten Chinese cities made the top 50, according to the list. The five cities and metro areas of Wuhan, San Francisco-San Jose, S?o Paulo, Munich, and Cape Town were featured this year for their rapid rise in scientific research with separate tables ranking their top 10 institutions respectively. 

The following are the top 10 global science cities:

10. Chicago - Naperville - Elgin

Country / Region: United States of America (USA)

FC 2017: 759.71

AC 2017: 1,852

Share of country/region FC (%): 3.9%

Externally collaborative AC (%): 83.0%