Wednesday, February 17, 2010

314. A Cantometric Study

Last month, purely by accident, while browsing the Web, I came across a remarkable paper based on, of all things, Cantometrics.* It's actually a Master's Thesis, from the University of London and Imperial College, and is surprisingly recent, dating from March 2006. I assumed I was aware of everything going on in the world of Cantometrics, but this one took me by surprise. It's called Finding the Blues: An Investigation into the Origins of African American Music. The author is a young man named George Busby, whose work was supervised by Dr. Armand Leroi, a noted biologist with a special interest in world music and Cantometrics. To my great surprise, delight and astonishment, Busby, with the assistance of statistician Jonathan Swire, has done a truly exemplary job.

Normally I would not look forward to reading a Cantometric study done without my assistance, because the system is not as straightforward as it might seem and there are certain quirks and hidden pitfalls that must be taken into consideration before any meaningful statistics can be produced. Amazingly, Busby and Swire figured out literally all the problems and were able to iron out just about all the kinks, a job that involved, among other things, recasting certain parameters entirely. I would do things a bit differently, but I have no complaints about the approach they took. In fact, as far as I'm concerned, this paper can stand as a model for how to use Cantometrics effectively as a tool for cross-cultural research. I'll call your attention specifically to the Appendices, starting on p. 28, which contain a wealth of extremely useful information on the background of Cantometrics, its methodology, its problems, what makes it controversial, how it works, and how to get the most out of it.

For someone new to this methodology, Busby seems remarkably perceptive in understanding the value of Cantometrics and evaluating both its strengths and weaknesses. Here are some excerpts from his paper that I found particularly relevant:
The phylogenetic study of song requires song analysis in a way that can produce readily comparable data. A profile of numbers for a song (which refers to its characteristics) needs to be produced so that its similarities to other songs can be quantitatively investigated. This is analogous to the production of genetic profiles from DNA for investigating evolutionary hypotheses. Fortunately data of this type are already available from a world sample of folk and tribal music collated for the Cantometrics experiment of the 1960s. . .

The algorithm shows clearly that multivariate analysis of the Cantometric data can produce structure that matches closely to geographical, historical and cultural populations. Note also that some clusters are highly biased to one cultural region while others contain a mixture, for example in K = 7, cluster 4 is mainly AI, while cluster 7 has a combination of styles, AAF and OEU, in almost equal proportions. It must be inferred from these results that the song styles from the two regions are similar. . .

Alan Lomax developed Cantometrics with the conviction that song style around the world could be explained by the culture in which it was produced. His idea, that song is a measure of culture, was a bold one. At the time, it had its critics. The methodology was questionable, the analysis perhaps na├»ve (see appendix A1). However, the present study has sought to overcome many of these problems, particularly regarding our removal of a priori cultural information from the analysis and the quantitative techniques used in the cluster analysis. In the light of recent cultural evolutionary research, Lomax’s idea now seems prescient. . .

From the initial analysis they had the two broad types which, as the study evolved, were divided into subsets of types depending on these factors of song style performance. Different combinations of levels of factors gave different profiles and so songs could be quantitatively rated on how similar they were. As well as the measures mentioned above, the songs were graded on their cohesion, wordiness, metre, embellishment and type of voice (clear or slurred). Factor analysis produces clusters of songs with similar profiles for these traits. Interestingly, these clusters matched, albeit very generally, geographically and historically similar areas. That is to say, song styles from African Hunter societies were more similar to each other than they were to Amerindian or European songs. This crude system was improved and eight major taxonomic concepts were discovered, each with different scales beneath them (table A1.1.).

Musicologists were already aware of these world song style regions, so it’s not wholly surprising that Cantometrics confirmed this. However, it is important to note that it did find these areas in a quantitative and scientific fashion (Merriam 1969).
There is much more of interest in this paper, not the least of which is what Cantometrics enabled the author to discover about the relation between African music, African American music and the Blues, which is, of course, the principal topic. It pleases me enormously to see such an outstanding piece of Cantometrics-based research by a young person who understands the value of this much maligned and little understood methodology.

Mr. Busby's current activities are documented on the very interesting Capelli Group website, where it soon becomes clear that he is, very sadly, no longer involved in musicological studies. Though he is now pursuing an equally interesting -- and not unrelated -- field: evolutionary genetics. I wish him well and hope that someday we might find a way to work together.


*Cantometrics is a computerized method for the comparative study of world vocal music, conceived by Alan Lomax and developed by Lomax and myself during the summer of 1961 (yes, I am THAT old :-\). For more information, see Post 76 et seq.

No comments: