The study that shows effects of using visuals in presentation neglects to lead the readers to the famous conclusion.

Note: This is part 4 of a series of posts reviewing some of the origins of scientific claims that compare text vs visuals. Access part 1 here.  Access part 2 here. Access part 3 here.

If you would like to follow along, you can find the original article that I’m reviewing from University of Minnesota website.

The paper we are looking at is titled, “Persuasion and the Role of Visual Presentation Support: The UM/3M Study” prepared by Douglas R. Vogel, Gary W. Dickson, and John A. Lehman.

We have been talking about various quantitative claims that many use to validate power of visual communication. While I don’t disagree about the power and potential of using visuals to convey a message, some of the cited references had some hazy origins. Since my work depends on scientific and medical accuracy, I constantly read journal articles and attend scientific talks. I am very familiar with the general setup of a research paper.

Last time we took a look at the second part of the results of a paper that claims that using visuals will make a presentation 43% more persuasive. The study continues to be highly questionable while showing graphs and charts with no numbers. The authors spend time talking about statistical significance of the results, but the p values are expressed in arrows. My mass-spectrometrist boyfriend asked about error bars. What error bars?

To add to the confusion, the study mixes control and variables, makes connections to data points that are unrelated, show the same graph with different results without explanation, and comes to a conclusion that color overhead transparencies are the best.

To keep on track, this study was supposed to compare how students reacted to presentations with or without visuals.

Here’s my approximate interpretation of how this study is set up. I will use a very familiar example: comparing chocolate and vanilla ice cream:

UM3Mstudy43percent

After the results are shown (kind of) and left many questions unanswered (while answering topics that were not questioned), the paper then goes onto give advice about how to give a good persuasive presentation. Let’s take a look.

The Model of the Persuasion Process (Discussion?)

I skipped figure 1 in the M/M because it made no sense to me. Now they want to compare it to the next figure, figure 10. So, let’s put them side by side.

figure 1, Vogel et al. 1986

 

figure 10, Vogel et al. 1986

 

OK, I must admit, I still don’t get it. I think the figure is combining directional flow (arrows) with increase in strength/quality (arrows). They also say that the width of the arrows meant different things. Wow.

The study states,

“The knowledge presented in Figure 10 should allow a presenter to selectively employ visual support depending on the outcome that is desired,

e.g., if the goal is to enhance comprehension and retention,

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support of a different kind may be called for than if the focus is on creating audience attention.
(Vogel et al, 1986. p.15)

Presentation support is visual support in this particular study. Did it just say find different ways (ie, NOT visuals) if you want your audience wants to understand and remember the materials? There are images that grab attention, and there are images that instruct and teach. I also don’t recall the study making a distinction between types of images.

What this study wants you to do when preparing a presentation

The study lists advice for you. My personal comments in green.

  • Use visuals to “look” better for the audience. Somehow we talk more about speakers than the actual visuals.
  • Visuals will improve audiences’ attention, comprehension, yielding/agreement, and retention. Yes of course. How they came to such conclusions from the graphs in figure 3 or 9, we will never know, but these are generally true.
  • Color graphics are better. Like we said in previous post, this claim is totally unsupported. Relationship between color and persuasion is not discussed in the study.
  • Enhanced graphics increase information density. Yes it’s true….When did the paper talk about qualities of graphics? Oh right, never.
  • 35mm slides are perceived to be more professional...if you say so. Maybe that’s what the arrows were trying to say.
  • Overhead transparencies makes the presentation “seem” more interesting. Seem more interesting? I think a presentation needs to be interesting even before visuals come in.
  • Increase attention. This is bullet #2 in the same list. Don’t elongate list like this.
  • Color affects audience comprehension. Oh really? Sounds awful similar to bullet #3.
  • Use image enhanced graphics selectively and carefully. What? Sounds like bullet #4.
  • Yielding-agreement and enhanced perceptions of the presenter. Why are we repeating #1 and #2?
  • Color enhances retention. I think they repeated everything twice by this point.

You think we’re done? Oh no, the next section is sure to surprise you when the authors take the readers through an unexpected turn of events! Next installment: The authors begin a new experiment in the last 3 pages of the article.

Please share your thoughts and questions in the comments below. I’m flabbergasted! Is this surprising to you, or is this what you expected?

Part 1: Abstract and Introduction
Part 2: Results, part 1
Part 3: Results, part 2
Part 5: New experiment begins and wrap-up