visible artifacts

By: Chris Malek

Oct 11 2008

Category: Summaries

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Tufte, E. R. (2003). Cognitive style of PowerPoint.  Cheshire, CT: Graphic Press.

Tufte’s article is really a critique of poor presentation skills, and a plea for better reasoning skills about information.  He asks that presenters and audiences do not simply accept PowerPoint’s default templates and modes as the proper way to conduct serious presentations of evidence: “The evidence indicates that PowerPoint, compared to other common presentation tools, reduces the analytical quality of serious presentations of evidence.”  He ends his article with a suggestion for how such presentations should be carried out: “serious presentations might well begin with a concise briefing paper or technical report (the 4-pager) that everyone reads (people can read 3 or 4 times faster than presenters can talk).  Following the reading period, the presenter might provide a guided analysis of the briefing paper and then encourage and perhaps lead a discussion of the material at hand” (p. 30).

Note that Tufte is specific about the kind of presentation he means: a serious presentation, “with explanations ot understand, evidence to evaluate, problems to solve, decisions to make, and in several examples, lives to save” (p. 27).  Kinds of presentations that Tufte is not talking about:

• the performance (David Byrne), Machine Project presentation
• the interactive demonstration (computer education)
• the marketing pitch (Steve Jobs at MacWorld)
• the political speech (offshoot of marketing pitch)
• other?

Five steps to better serious presentations

He gives these maxims as what should guide good, serious presentations.

Assume that your audience is intelligent, and found your presentation in principles of respect for them.   Use the core ideas of good teaching: “explanation, reasoning, finding things out, questioning, content, evidence, credbile authoirty not patronizing authoritarianisim” (p. 7).
Strive to be as clear as you can.  Be precise.  Use enough words (spoken and written), images, and information graphics in the right combination to clearly and precisely convey the information.   Give people all the data they need to make evaluations and decisions; don’t let the medium dictate how much you give.
Be honest and accurate.  Don’t distort the data.  Be respectful of human strengths and weaknessess.  For example, it is hard for humans to compare areas of objects (so pie charts are bad), but we’re good at  being able to compare sets of data (e.g. images) with our eyespan).
Allow your audience to explore, evaluate and discuss the information.
Use appropriate media to support the level of detail you need to do this.

Properties of computer projected presentations

Intrinsic characteristics:

1. LCD projectors have low resolution, hence low data density.  This determines the total amount of information we can convey on any one slide, and it’s not much.  This makes text and information graphics on slides be of limited usefulness.  High information density images, however, are worth it.
2. Projected things need to have large type so that people in the audience can read it.   There are only so many words we can expect to fit on a page and actually have people be able to read them.
3. Slides are presented sequentially and transitions are driven by presenter, not the audience.   The audience can’t go back to previous slides to review (without interrupting the presentation) or go forward to reconnoiter.  They can’t explore the information that’s being presented, and so they are put into the role of passive receptors rather than active learners.

Accidental characteristics:

• bullet lists
• hierarchies
• bad graphics
• transitition effects
• templates
• wizards
• etc.

All of the accidental charactersitics are avoidable, while the intrinsic characteristics are not (without much effort), and so it is those intrinsic characteristics that determine the cognitive style of PowerPoint.  That accidental characteristics caused serious problems as well in the Columbia slides are more a function of social consensus, lack of skill and lack of effort.

My critique

Much of what he complains about as the product or fault of PowerPoint I think is the lack of skill in the presenter in organizing information and presenting it.  He addresses this particular critique with a paraphrase of George Orwell: “PowerPoint becomes ugly and inaccurate because our thoughts are foolish, but the slovenliness of PowerPoint makes it easier for us to have foolish thoughts,” (p. 27) and “To make smarter presentations, try smarter tools.” (p. 28) implying that simply using PowerPoint can make you a bad presenter.

I think that skilled craftsmen can make quality work even with poor tools, while poor craftsmen can’t make quality work even with good tools.  Presenting at all is a skill, something that requires natural talent, training, a lot of practice and a lot of self-reflection.   You need to be able to organize information into a story that can be told sequentially (in time) and still make sense; you need to be able to tailor that information to your audience; you need to tailor your presentation to your goal — teach, inform, persuade, entertain;  you must be able to entertain your audience even if your goal is something else.   I think that if a skilled presenter is conscious of the intrinsic limitations of computer projected media, and can avoid or use to her advantage the accidental qualities, she can use PowerPoint (or Keynote, etc.) to advantage.

Secondly, I think he over-simplifies the kind of data one might need to convey in a serious presentation (video and images and sound, websites, technical demonstrations, visiting websites) and ignores how valuable a common focus is when doing collaboration.

Edward Tufte

Edward Tufte is a primal force in information visualization, and his books are referenced commonly in papers which propose or use visualization tools or techniques.  Google Scholar lists 2208 cites for The visual display of quantitative information, 1395 for Envisioning Information, 800 or so for Visual explanations.  Prof. Tufte (he is professor emeritus at Yale University) has made a mission of educating people on how to honestly, clearly, and effectively present information.