Chapter Seven: Visual Presentations and PowerPoint
In this chapter we're going to discuss some general visual principles for live technical presentations and then
consider the most common format for these presentations today--PowerPoint.
Visual Presentations--General Principles
It's easy to forget sometimes that when you're doing a live presentation, you're creating a visual document. It
just seems like a different medium because it's using the dimension of time as well as the three spatial
dimensions. But if you were to freeze-frame your presentation or take still photographs of it, you would see
tableaux or scenes that you're presenting to your audience. It pays to consider the effectiveness of these
tableaux as vehicles for technical information. Let's begin with a recent presentation that I made, a tableau
of which appears in Figure 1:
Figure 1: Phone interview dramatization for 2006 GSA conference, NMT
This is a dramatization of a phone interview for an academic job. Can you guess which part I'm playing? The
cues helping you make an educated guess that I'm the interviewee include the divider, which symbolizes a
separation in space, the fact I'm by myself holding a handset to my head, and the fact that I'm gesturing as if
I'm explaining. Meanwhile, the "committee" on the other side of the divider is gesturing as if they're listening
and evaluating.
The props, the gestures, these are all media of visual communication. Another medium you can't see in this
tableau is the handout that each member of the audience has in their hands listing important points for
preparing and performing in a phone interview. The audience can constantly compare what they see in the
dramatization to what is written in the handout.
You can't evaluate the effectiveness of our presentation without thinking about (a) the audience, (b) the
purpose of the presentation, and (c) genres or media we had to choose from when preparing this
presentation. We could have given a PowerPoint that listed all the points in our handouts. But learning
interviewing skills takes practice, and it's easiest to practice behaviors that you've seen modeled for you. So,
we chose the dramatization to model both good and bad behaviors for phone interviews. We felt this
medium was the most effective because our audience was graduate students getting ready to do job
interviews, and we felt they needed an engaging presentation (drama) that would model behaviors they
might need to adopt in a very short time period, perhaps even just a few days. Because it's easy to forget
small details in a dramatic presentation, we reinforced our points with a second medium (handout) that
would serve as a memory jogger when the students were preparing for their interviews.
Our GSA presentation is just one small example of the multiple visual considerations that go into preparing a
technical presentation. As you can see, the presentation is the primary medium, and that will always involve
you getting up in front of other people and talking to them. The secondary media that reinforce your points
and assist your audience's learning and memory are many but can include PowerPoint, handouts, video,
posters, visual aids for the audience to handle or pass around, and dramatizations. Here are some general
principles of presentation to keep in mind no matter what your secondary media are:











Dress professionally
Speak loudly, clearly, and slowly
Direct your gaze to every section of the audience at least once every 2 minutes
Control body language to exclude distracting behaviors such as rubbing the back of your head or
your nose
Control vocal presentation to limit tics such as "um" and "like"
Time your presentation to conclude at or under the alloted time
Choose the best reinforcing media for the audience and situation
Arrive early to greet attendees and make sure your microphones and other technical equipment are
bug-free
Try not to step into your screen, if you're using projection
Limit humor, and only use humor that applies directly to your subject of presentation
practice, practice, practice. I'm sorry, did you just say, "Practice"? Why, yes, I did, and once more
with feeling: Practice!
These suggestions are all aimed toward a few principles that improve the chances of your audience
accepting what you have to present: establishing your ethos (credibility), keeping the audience's attention,
and focusing their attention on the information you're presenting, not on the presentation itself. There are no
substitutes for preparation and practice. A rule of thumb for preparation is 8x. If you have a 15-minute
presentation, it should take you at least two hours to prepare it, assuming that you have all the data ready to
go. Preparation includes doing audience analysis and selecting the appropriate reinforcing media. The rule
of thumb for practice is 3x. You should practice your presentation at least three times before you give it,
and the final of these runs should include setting up all of the technical equipment you will need. It is an
excellent idea to videotape yourself giving your presentation. Once you have been through this
experience, your nervousness will decrease and you will eliminate many of your tics and distracting
gestures.
PowerPoint
Now that we have discussed the primary medium of visual presentation, we need to examine the visual
rhetoric of the most popular reinforcing medium: Microsoft PowerPoint. Edward Tufte launches many
germane criticisms of PowerPoint in his booklet, "The Cognitive Style of PowerPoint." His basic point can be
summarized as follows: Conway's law says that no medium of presentation can transcend the culture that
made it. PowerPoint was created within the software industry, which does two things: coding and marketing.
Therefore, PowerPoint is designed to "sell" ideas that must be presented in shorthanded, relentlessly
sequential bits. It therefore hampers attempts to lay out complex ideas panoramically, and all "serious"
technical presentations involve complex ideas that must be viewed panoramically to be adequately
understood. A "serious" technical presentation is one that is required to inform a decision upon which
significant amounts of resources or safety of personnel or consumers depend. In these situations, Tufte
recommends a technical report in the following format: a handout consisting of an 11x17 sheet of heavy
paper folded in half widthwise to create four 81/2 x 11 pages. Tufte claims that this higher resolution of this
format presents the equivalent of anywhere from 50 to 250 PowerPoint slides; it has the added benefit of
being portable and reusable, which a PowerPoint is not (unless and until it can be posted on a website
whose URL is communicated to the audience).
To illustrate the poor applicability of PowerPoint to serious presentations, Tufte references Peter Norvig's
"reconstruction" of the Gettysburg Address as a PowerPoint. It is truly hysterical. On a much more somber
note, his brochure contains an analysis of the PowerPoint that Boeing presented to NASA officials when
asked for a risk assessment of damage to the Spaceshuttle Columbia after loss of "ramp" or insulating foam
in takeoff. The PowerPoint obscures the fact that Boeing's models have failed to determine whether or not
the shuttle will burn up on re-entry; consequently, their final assessment of "we have no evidence that it will
blow up" is read as "it probably won't blow up," and NASA decides to land the shuttle without repairing the
wing, with disastrous consequences. Tufte makes a convincing argument that part of the fault for this
travesty lies with PowerPoint itself and the way it hampered Boeing's ability to communicate the technical
data from their models to the NASA engineers.
While Tufte's criticisms of PowerPoints and attendant solutions are worthy, they assume an ideal situation in
which our budgets include four-color printing costs for handouts for audiences up to 200 people. Tufte is
also not particuarly concerned with paper waste or postability to the internet. So, given that many of us will
have to keep making PowerPoints for some presentations, how can we adapt his principles to try to use the
medium most effectively? What follows here is a list of suggestions. I'm also including a link to a PowerPoint
presentation I have created that illustrates and annotates further cautions when using PowerPoint:
1.
2.
3.
PowerPoint is terrible at presenting text. Don't present text beyond titles, captions, and perhaps
few-word bullets for your Overview slide, if necessary.
PowerPoint can be used as a slide projector for low-resolution graphics such as .gifs and .jpgs.
Make sure all captions are presented at 16 pt. at a minimum for readability.
Whenever possible, offer a handout to accompany your presentation with data and references. Do
NOT just print out the slides. Make a technical handout that goes significantly beyond the
PowerPoint in terms of data presented.
Exercise
Use the Auto-Content Wizard in PowerPoint (Click "New" under the File menu and then select "From the
Auto-Content Wizard" under the New submenu in the window that pops up to the right) to generate a
presentation on a technical problem or issue in your major field or on a topic of interest to you. I repeat,
technical. You can use the "Presenting a Technical Report" template, but there are others that you might
prefer, including "Communicating Bad News" or "Presenting a Strategy." Leave me notes in the notes fields
for each slide about your experiences using the Auto-Content Wizard. Did it help you invent your
presentation? Did it let you say what you wanted to say? How easy was it to customize? Discuss these
topics and more in the notes fields.