A digital bookshelf: original work on recommender systems

I spent the better part of the 1989-90 academic year at Columbia University, in the NLP group headed by Kathy McKeown as a visiting graduate student. I had recently begun my graduate studies and my idea was to work on statistical models to improve human computer interaction. I had heard of neural networks, read the recently published PDP book and worked through its examples (there was a 5 1/4″ floppy disk included!), and went to a Summer school on connectionist models and neural architectures organised by Boston University in Nashua NH, taught by Steven Grossman, Robert Hecht-Nielsen and some others (the school was very focussed on the ART architecture). I built a connectionist crossword puzzle generator in Prolog which given a lexicon almost managed to build a crossword puzzle.

That year was fruitful in several ways. My most important task for myself was setting up experiments on recommender systems. I collected data through a questionnaire, and I ran statistical experiments on .newsrc files on the systems I had access to. I visited Bellcore in Morristown, where my mentor Don Walker invited me to give a talk to his lab which I believe included Will Hill who later worked on this sort of thing. I had by then written a paper on the “Digital Bookshelf” which was promptly rejected by the 1990 INTERACT reviewers because they held that building a recommender system would interfere with users’ privacy and integrity.

When I came back to Stockholm I wrote a tech report to describe the idea. Later, I wrote a more complete report, when I worked at SICS. I only published it in 1994: I brought it to that year’s SIGCHI and distributed it to several friends there. Martin Svensson, one of my colleagues at SICS later picked up similar thoughts and wrote his dissertation on Social Recommendation Systems, and by then I started to regret that I had not worked more on developing the ideas further! I blame those reviewers for the 1990 INTERACT! (I probably should not have opened that discussion: I included a section on privacy aspects in the paper.)

  • The 1990 Tech Report: Jussi Karlgren. 1990. An Algebra for Recommendations. The Systems Development and Artificial Intelligence Laboratory. Working Paper No 179. Department of Computer and Systems Sciences. KTH Royal Institute of Technology and Stockholm University.
  • The 1994 Tech Report: Jussi Karlgren. 1994. Document Behaviour Based on User Behavior—A Recommendation Algebra. Tech report T94:04. Swedish Institute of Computer Science. (Or here, if that link breaks.)