The Interaction Equivalency Theorem: Research Potential and Its Application to Teaching Terumi Miyazoe, Associate Professor Tokyo Denki University Terry Anderson, Professor Athabasca University Introduction This paper aims to overview the Interaction Equivalency Theorem posited by Terry Anderson (2003). It clarifies the position of the theorem in distance education and provides a definition that includes its essential composites. Two research studies are introduced: a meta-analysis on the theorem to show its validity and an empirical research study using the theorem to demonstrate an application of the theorem in teaching and designing. The theorem is useful when analyzing the existing instructional design(s) of a specific learning context and deciding on the optimal interaction design that meets the needs and limitations of the learning context. This paper is an update of two 2010 journal papers by the same authors (Miyazoe & Anderson, 2010a; 2010b). Background Location in the Distance Education History In this paper, interaction is defined as “reciprocal events that require at least two objects and two actions. Interactions occur when these objects and events mutually influence each other” (Wagner, 1994, p. 8). This definition is the one used by Terry Anderson because of its simplicity and inclusiveness (Anderson, 2003). Historically, the “Three Types of Interaction” model (Moore, 1989) is regarded as the first systematic definition of interaction. This model defines critical interaction in educational contexts as having three essential components―learner–content, learner–instructor, and learner–learner interaction. The third element of learner–learner interaction may not appear new to present-day readers. However, at the time when Moore configured this model, online information delivery was not as developed in primary independent study modes of distance education and learner–learner interaction was a “new dimension” and a “challenge” (Moore, p. 4). The Modes of Interaction In their extension of Moore’s interaction model, Anderson and Garrison (1998) advanced an interaction framework called the Modes of Interaction. Aside from the three interaction dyads proposed by Moore, the three dyads of teacher–teacher, teacher–content, and content–content interaction were also conceptualized as indispensable components to support deep and meaningful learning in online and distance education. This extension is propelled by the transition from the traditional distance education delivery system to the currently available, digitally networked learning environment, in which networks afford and can realize a much greater degree of interaction. Digital resource sharing, teacher networks and teachers’ active involvement in making and sharing digital instructional materials are examples of teacher–teacher and teacher–content interaction. Another critical point is that Anderson considers both human and nonhuman interactions are integral components that help create a high-quality educational experience. This perspective highlights the new nature of student–content and even content–content interaction, in which students actively work online with artificial intelligence programs, the latter working together by transferring data multi-directionally to support online learning. The Interaction Equivalency Theorem The Interaction Equivalency Theorem posited by Anderson (2003) is the core of this paper. By extending the Modes of Interaction, the theorem aims to provide “a theoretical basis for judging the appropriate amounts of each of the various forms of possible interaction.” The main features of his theorem are condensed into the following two theses: Thesis 1. Deep and meaningful formal learning is supported as long as one of the three forms of interaction (student–teacher; student–student; student–content) is at a high level. The other two may be offered at minimal levels, or even eliminated, without degrading the educational experience. Thesis 2. High levels of more than one of these three modes will likely provide a more satisfying educational experience, although these experiences may not be as cost- or time-effective as less interactive learning sequences. 27th Annual Conference on Distance Teaching & Learning For more resources: http://www.uwex.edu/disted/conference Copyright 2011 The Board of Regents of the University of Wisconsin System 1