Ngram Game Theory
Here is a chart from Google’s Ngram showing the frequency of “Game Theory” and “Decision Theory” over the last few decades in published books. Interesting to note the drop from 1970s through the 80s that then re-emerges, I imagine, due to the rise of modern computers–all while “Decision Theory” has a small hump in the 70s and undergoes a steady decline.
The discussions of matrices also seem less important now than they must have seemed previously, while the discussions of decision trees has become increasingly important. Perhaps “decision trees” are also a synonym for flowcharts?