If you are into neural nets, you know about the Laboratory of Computer and Information Science at the Helsinki University of Technology. One of the Department's most important professors is Teuvo Kohonen, the creator of the self-organizing map algorithm (SOM). The deparment also provides one of the best shareware downloads (SOM Toolbox) for using the SOM--it runs in the MatLab environment.
As I discussed in a previous blog (4/01/09), in 2003 I published an article in Symbolic Interaction exploring how qualitative researchers can use the SOM to conduct grounded theoretical investigations of large, complex, numerical databases. For the next six years, I sat around hoping someone other than myself would find the idea interesting and useful. Nothing happened! I know that publishing on mixed methods seldom goes anywhere, but I thought that, with the incredible advances taking place in complexity science and informatics and the internet, qualitative researchers would eventually consider the idea.
They have yet to do so. But, perhaps the latest article by Nina Janasik, Timo Honkela, and Henrik Bruun of the Helsinki University of Technology can change people's minds.
The title of their article is TEXT MINING IN QUALITATIVE RESEARCH. The purpose of the article is to show qualitative researchers how to apply the SOM to qualitative data.
Here is the abstract:
The article provides an introduction to and a demonstration of the self-organizing map (SOM) method for organizational researchers interested in the use of qualitative data. The SOM is a versatile quantitative method very commonly used across many disciplines to analyze large data sets. The outcome of the SOM analysis is a map in which entities are positioned according to similarity. The authors' argument is that text mining using the SOM is particularly effective in improving inference quality within qualitative research. SOM creates multiple well-grounded perspectives on the data and thus improves the quality of the concepts and categories used in the analysis.
When I read this article I was more than a little excited! I cannot tell you how much time I spent between 2001 and 2003 at the Helsinki website trying to learn about the SOM and figuring out how to use the SOM Toolbox. Let's just say it was a lot and leave it at that. I also cannot tell you how much respect I have for the researchers there. Incredible research; they make their work and software freely available to others. It is just fantastic.
I also have to say that Janasik, Honkela, and Bruun do an excellent job addressing the limitations of my 2003 article--in particular, how I did not go far enough in demonstrating just how useful the SOM is for qualitative work. As such, I agree completely with their critique. And, I agree that any qualitative researcher trying to figure out how to do their work in the digital age should read this article.
Key Words: grounded theory • constructivism • self-organizing map • text mining • document interpretation