World Shares of Publications of the USA, EU-27, and China Compared and Predicted using the New Interface of the Web-of-Science versus Scopus

The new interface of the Web of Science (of Thomson Reuters) enables users to retrieve sets larger than 100,000 documents in a single search. This makes it possible to compare publication trends for China, the USA, EU-27, and smaller countries, with the data in the Scopus database of Elsevier. China no longer grew exponentially during the 2000s, but linearly. Contrary to previous predictions on the basis of exponential growth, the crossover of the lines for China and the USA is postponed to the next decade (after 2020) according to this data. These long extrapolations, however, should be used only as indicators and not as predictions. Uncertainty in trends can be specified using the coefficient of determination of the regression (R 2 ) and confidence intervals. Along with the dynamics in the publication trends, one also has to take into account the dynamics of the databases used for the measurement.