A Key Word History of Marketing Science (co-authored with Carl Mela and Yiting Deng) has just been accepted at (where else?) Marketing Science. The idea behind the paper is to use the key words authors have assigned to papers published over the past 30 years in Marketing Science (the journal) to track changes in marketing science (the field). By “key words” we mean the small set of descriptors assigned to papers when they are published, similar to the JEL classifications used for papers in econ journals. At Marketing Science, however, authors are free to make up their own key words.
Our approach to inference in this paper is almost entirely model-free—that is, for most of the analysis, we plot raw data and then draw our inferences directly with defining a formal model (we bring in multivariate analysis—cluster analaysis and multidimensional scaling—but the bulk of our analysis is based on the data themselves). I like this approach, especially for a descriptive paper like this.
Two of my favorite plots from the paper are Figures 4 and 5. In Figure 4, we show new key words appearing each year; some of them sticking around in future years, but most never appearing again. It's clear that the rate at which new key words appear in the journal is growing (we discuss reasons for this in the paper).
But even though the rate of new key word is increasing, the likelihood of hitting on a new key word that sticks around for years to come is decreasing, suggesting the field is maturing. This is shown in Figure 5.
One of the recurring themes in the paper is the dominance of game theory as a research paradigm in marketing. Game theory first entered the top 10 (in terms of share of papers using that key word) in the mid-90's and has been extremely popular ever since. Interestingly, in our cluster analysis, we find game theory doesn't group well with other key words. Rather, it seems to function as a uniting framework that brings together a wide range of topics and research methods. Or as Carl puts it, it is "the one ring to rule them all."