The Shrinking Horizons of Computational Linguistics

Abstract

Understanding language is one of the great challenges of science, and languagerelated technology is one of the great opportunities of Information Technology. Consequently, many different kinds of researchers work on language issues. Within the computer science community, language is studied by the “ACL community,” by which I mean researchers who regularly publish in Association for Computational Linguistics (ACL) venues, such as the journal Computational Linguistics and ACL conferences. But language-related research is also carried out by researchers in other areas of computer science, including knowledge representation, cognitive modeling, vision and robotics, and human–computer interaction communities. Additionally, there are even more people outside computer science who study language, including linguists, psycholinguists, philosophers, and sociolinguists. This is fine; understanding language and developing language technology are huge problems, and it is very useful to have many research communities from diverse backgrounds working on language. This will be especially true if the different research communities are aware of each other, so they can share insights, observations, problems, and so forth. Unfortunately, my impression is that the ACL community is much less interested in research with other language-related research communities than it used to be. This impression is mostly based on discussions I have had with researchers who are on the border between ACL and another language-research community. Several such people have told me that whereas ten years ago they occasionally submitted papers to ACL venues and attended ACL conferences, now they do not bother, because they believe that the ACL community has no interest in their research. In attempt to quantify this insight, I have analyzed citations from papers published in Computational Linguistics in 1995 and in 2005. Specifically, I extracted all citations from Computational Linguistics (CL) articles (excluding book reviews) in these years to journal papers. I then classified the cited journal papers into one of the categories shown in Table 1; whenever possible this classification was based on the subject category assigned by ISI Journal Citation Reports (JCR) to the cited journal. For example, a citation of a paper in Cognitive Science would count as a psychology citation, since ISI JCR classifies Cognitive Science as “Psychology, Experimental.” I counted citations myself, rather than relying on ISI JCR’s count, as there were some mistakes in JCR’s counting. I also created my own “other NLP and speech” classification (that is, references to speech and NLP