How do firms and inventors move through knowledge space as they develop their innovations? We propose a method for tracking patterns of exploration and exploitation in patenting behaviour in the US for the period since 1920. Our exploration measure is constructed from the text of patents and...

Strong evidence has been emerging that major democracies have become more politically polarised, at least according to measures based on the ideological positions of political elites. We investigate whether the general public (`citizens') followed the same pattern. To this end, we propose a...