Background
Douglas R. Vogel is a professor and chair of Information Systems at the City University of Hong Kong. He is recognized worldwide for his research in areas like group support systems, MIS and collaborative information systems. Although most Presentation Professionals would not know Vogel by name, he has played a key role in developing our understanding of how visuals support persuasion in a presentation setting.

After graduating with a B.S. in electrical engineering from Montana State University, Vogel earned an M.S. in computer science from UCLA in 1972 followed by a Ph.D. in Business Administration/MIS from the University of Minnesota in 1986. While working on his Ph.D., Vogel was an assistant professor of MIS and the research coordinator for the Management Information Systems Research Center (MISRC) at the University of Minnesota.

In 1986, Vogel submitted a doctoral thesis paper to the faculty of the UM Graduate School entitled: “An Experimental Investigation of the Persuasive Impact of Computer Generated Presentation Graphics.” Later a summary of this experimental investigation was published as a Working Paper Series entitled “Persuasion and the Role of Visual Presentation Support: The UM/3M Study.”

Vogel’s thesis paper is by far the most comprehensive look into the effectiveness of presentation support I have found thus far. The paper is 232 pages long, excluding the appendices and contains an abundance of information not included in the 19 page UM/3M summary report. Vogel did an extensive literature review, drawing from scholarly work in speech communication, social psychology and persuasion theory.

The overall investigation was conducted in four phases. Phase I involved the literature review and the identification of underlying theory applicable to the development of a model of persuasion. There are many theories of how persuasion occurs, but Vogel decided to use the message learning approach (Hovland, et al., 1953 and William McGuire, 1969) which describes persuasion as a function of the following components:

attention… comprehension… yielding/agreement… and retention …. culminating in action.

In other words, ultimately persuasion is measured by the audience taking a desired action… however anything that enhances any of the components leading up to that action has a potential to impact the overall persuasive effect.

Phase II involved developing theories and a model of how certain characteristics of visuals would impact persuasion overall as well as the individual components. In this phase, Vogel, individuals at 3M (financial sponsors) and others discussed what characteristics of computer graphic visuals would be interesting, relevant and “do-able” from a research perspective. Vogel wanted to make this study a foundational work that built on the limited research that had already been done and that could be used to launch additional studies.

Phase III was a pilot study of 150 subjects that tested the initial model. Based on the results of the pilot study, the model was enhanced and refined.

Phase IV consisted of the final study itself that was conducted with 335 junior level business students at the University of Minnesota. The remainder of this article will focus on the design of this important study. The results will be presented in Part II.

Persuasion Process Model
This is the theoretical model of persuasion Vogel used for the study. This model was developed from his historical research and was then adapted following the pilot study. The Phase IV study was designed to test the assumptions of this model.
Vogel theorized that many factors would influence the components of persuasion. Consequently, he wanted to be able to assess the impact of all of these factors and examine how they were moderated by several different types of visual support. Vogel anticipated that various audience characteristics, as well as perception of the speaker, would both have direct impact on the components of persuasion. He also thought that persuasion would be impacted differently by different types of visuals. As a result, the study was designed to look at B&W versus color, text-based versus graphics-enhanced images, and 35mm slides versus overhead transparencies. Vogel also recognized that a number of variables had to be controlled in order to evaluate the impact of visuals. The study was designed to fix or control for the following variables: organizational culture and context of the presentation; the content delivered; the speaker; and the medium used.

Study Design
The study took place at various time points within a 10-week course at UM. During the second week of the course, a visit was made to the lecture classroom where all the students were together. The students were told that they would have an opportunity to sign up to participate in some time management seminars. The fictitious seminars would take 6 hours of their time and cost $15.00 each. Only the titles of the seminars were given (i.e. “Working Smarter” or “Fighting Procrastination”) and the students were told that the seminars would be given by time management professionals. After hearing this limited information, the students filled out a one page questionnaire (the pre-measure) to assess their interest.

In the fifth week of the course, 9 laboratory sections of about 35 students each were given a presentation about the seminars. There were eight “treatment” groups where different presentation visual types were used, and one control group where visuals were not used. In each group, the presentation was delivered by the same speaker who had been recorded on videotape. Vogel interviewed numerous speakers for this role and purposefully picked a person of “average” speaking ability. While the video was playing, a research member advanced the visuals in the eight treatment groups at predetermined points.

At the end of the 10 minute video, a questionnaire was again completed by the students. The same questions as before were asked along with questions to assess presenter perceptions, level of attention, agreement, comprehension and even the legibility of the visuals. Finally, after another 10 days had passed, the students were once more approached in the lecture hall by a research member and tested for comprehension in order to assess the retention of information presented.

Discussion
Vogel was extremely thorough in the design of this study. He carefully controlled for the variables that many studies in the use of visuals fail to control for. The use of a pre-measure several weeks prior to… and the follow-up test 10 days after… add to the credibility of his results. All visuals were “professionally designed” according to Vogel, however, they would not be considered very well designed by today’s standards. Part 2 of this post examines the results.