Can "Hot Spots" in the Sciences Be Mapped Using the Dynamics of Aggregated Journal-Journal Citation Relations?

Using three years of the Journal Citation Reports (2011, 2012, and 2013), indicators of change are developed involving only changes of more than one standard deviation above average. Two forms of change are distinguished: monotonic increases or decreases of citation intensity (cited or citing) and critical revisions of the a posteriori (2013) prediction in 2012 on the basis of 2011 data. Changes can be studied at the level of journals using the margin totals of entropy production along the row or column vectors, but also at the level of links among groups of journals by importing the transition matrices into network analysis and visualization programs (and using community-finding algorithms). The latter analysis improves on the former by being more fine-grained. Changes are found in the giant component representing the major disciplinary structures; and significant changes at the level of specialties are indicated in 52 components which are mostly on the applied side of the sciences and engineering.