CPSC 689/602--Spring 1997
Computer-Supported Cooperative Work


Paper Report

Title: Grounding In Communication
Authors: Herbert H. Clark and Susan E. Brennan
Citation: Perspectives On Socially Shared Cognition (pp.127-149), 1991
Reprinted in: Baecker, Pg. 222-234


In this paper the authors discuss a process called Grounding. They introduce this concept by first explaining its importance in communication. They state that the two people cannot even begin to coordinate without assuming a vast amount of shared information or common ground. And to coordinate on process, the two people involved need to update their common ground moment by moment. All collective actions are built on this common ground and its accumulation. Grounding takes different shapes and this depends upon two main factors: Purpose and Medium

Contributing to conversation divides into two phases -- the presentation phase and the acceptance phase. The authors add that it takes both phases for a conversation to be complete. They then discuss how each of these phases can get complicated. Specifically they talk about self repairs and embedding. The authors then go on to discuss the evidence needed in grounding. If we find some negative evidence, we repair the problem but if we dont we assume by default that we have been understood. People however seek positive evidence that they have been understood. Three types of positive evidence is explained: acknowledgments, relevant next turn and continued attention.

The principle of least effort is then presented and expressed in terms of two maxims, Quantity and Manner. The three problems that this principle poses are also discussed. The authors then move onto the Principle of Lease Collaborative Work effort and explain how this principle helps account many phenomena that the previous one didnt. The purpose of interest in conversations is to establish referential identity - that is the mutual belief that the addressees have correctly identified a referent. Some common techniques for the same such as alternative description, indicative gestures, referential installments and trial references are then discussed. Sometimes the verbatim content of the conversation is important. Here techniques such as verbatim, displays, installments and spelling can be used.

Thus, communication is a collective activity. It requires the coordinated activity of all the participants and grounding is essential for keeping that coordination on track.
Report prepared by: Abhijit Rele, Email: abhijitr@cs.tamu.edu
Discussion date: February 5, 1997            Report date: February 7, 1997