Cognitive cybernetics and human communication: The regulatory effects of prior knowledge

This dissertation describes the theory behind a new way to measure the effectiveness of human communication and an experiment designed to test the theory. The theory says that we must measure a message recipient's prior knowledge and use this information to improve messages in a cognitive cybernetic manner, that is, in a way that permits the prior knowledge of intended message recipients to control the complexity and redundancy of messages. Thus, the theory suggests that information theory should be modified to consider the effects of message interpretation by message recipients. The experiment, conducted over a three-year period at the University of Maryland, involved 398 undergraduate students. Interviews conducted in 1987 provided information needed for the pilot tests of 1988. The pilot tests showed how to design a two-phase experiment in which information from Phase 1 would provide data that could be analyzed by the Galileo multidimensional scaling system. The Galileo system's results were expected to show how a science article could be modified to make it either easier or more difficult for Phase 2 students to understand. The experiment's results indicate that students who read an "improved" article, in which all improvements were based upon Galileo results, scored significantly higher on a discipline test than those who read the unmodified article. The test scores of students who read a "degraded" article were not consistent enough to produce any conclusive results. In general, the experiment's findings support the theory that a multidimensional scaling system can be used to determine some of the effects of subjects' prior knowledge, and information concerning these effects can be used to improve the comprehensibility of messages to specific audiences. The ability to measure effects of relevant prior knowledge may be used to help explain why different people often get different meanings from the same message. To test the theory further, the study recommends using the Galileo multidimensional scaling system to measure the effectiveness of science textbooks.