Giving effective presentations

"I am a successful lecturer in physics for popular audiences. The real entertainment gimmick is the excitement, drama and mystery of the subject matter. People love to learn something, they are ‘entertained’ enormously by being allowed to understand a little bit of something they never understood before. One must have faith in the subject and people’s interest in it."

-- Richard Feynman

“I would drop everything to hear him lecture on the municipal drainage system.”

-- David Mermin, about Feynman

Good presentations have a thoughtful purpose

The first step to giving an effective presentation is to understand their value in achieving goals that are difficult to attain otherwise. Here are just some of the ways in which giving presentations can be be helpful:

  • to establish your expertise and to have your name recognized by the people in your field, especially independent to that of your supervisor

  • to encourage people to collaborate with you

  • to convince people to test your theory/prediction or to influence the research direction of others

  • to convince someone or a committee to target you for a job offer or offer you funding for your idea

  • to encourage people to cite your paper

  • to encourage people to use or contribute to software that you’ve developed

  • to receive useful feedback on preliminary ideas you may have

  • to “test” the talk itself, i.e., gauge audience reaction and points of confusion (based on the after-talk questions) to improve subsequent presentations (like a stand-up comedian at a small venue)

  • to simply help expand your audience’s knowledge about a particular subject and “tell them something you’ve learned”

  • to solidify your own thoughts about a topic!

Before you begin designing your presentation, you should be clear about one or more very well-defined goals you want to achieve by giving the presentation. For example, if you want to encourage people to use software you’ve developed, you’ll need to include slides explaining its capabilities and benefits to the community and as well as how to obtain and perhaps use the software. If you want people to test your theory, you should include slides suggesting how and why people might attempt this. If you want feedback on your ideas, you should further emphasize points of confusion / unresolved problems.

Note that you should not underestimate the value of giving presentations simply to establish your expertise and to promote your work. You may think that doing good research or writing a paper is enough. Unfortunately, this is usually not the case. Take the example of musicians: they cannot simply record an album and sit back expecting a devoted following of fans. They must instead earn their fans by going on tour and generating excitement about their music, perhaps starting out as a small and relatively unknown “opening act”; if they do a good job, the live act will encourage people to investigate the recordings. It is not much different for science; when you obtain a valuable result, you should go “on tour” and focus on disseminating it.

In summary, first decide on your goals for giving a presentation, then design your presentation around those goals.

Keep in mind context, audience, and length

When deciding on the goal of your presentation, keep in mind context, audience and length. In almost all cases, you should aim for a simpler presentation that just highlights the main concepts, but refers people to a paper or other document for more details. Meaning, the purpose of the presentation is to get people interested, not to tell them everything. This is especially the case if:

  • your presentation is short (e.g., 15 mins). Some of the worst presentations are those that try to accomplish too much in 15 minutes and end up doing nothing

  • your presentation is to a general / broad audience. Most people understand that they should simplify for a general audience.

  • your presentation is in a symposium with many other presentations. If you are giving an independent invited talk somewhere, you can assume that mostly people will be “present” for your talk. But if you are giving a talk at a conference where there were many talks before yours and many talks afterward, people’s brains are at 50% capacity due to information overload. Keeping your message simpler and using broad strokes really helps make your presentation stand out - with details saved for Q&A or by referring to a paper.

A longer, more detailed presentation is more appropriate when you have a long (e.g., 45 minute) time slot and when you are not in the middle of many other presentations (i.e., people’s brains are not already overworked).

Three good presentations

There is no single good presentation style. A good presenter doesn’t have to be authoritative or have a low voice. You don’t have to change your natural personality to give a good presentation. Here are some examples of people with different personalities nevertheless giving effective presentations.

  • Donald Sadoway (15 mins): formal, authoritative, high salesmanship yet also unconventional/creative with well-rehearsed spontaneity (e.g., use of blackboard): http://bit.ly/1WuEkeK

  • Walter Alvarez (22 mins): approachable, casual / unpolished yet poetic, with several tangents - yet inspiring wonder in the subject: http://bit.ly/2ov568E

  • Mick Mountz (12 mins): not necessarily a “natural speaker”, but makes a boring subject (packing boxes) fascinating through a great presentation structure and slides: http://bit.ly/2oSwO1y

None of the talks are perfect, and thinking about why will help your own presentation skills. However, the above talks are able to get the audience interested in the problem and invites them to briefly join them in their field of study. This is in contrast to talks that try to oversimplify concepts or try to sugar-coat them with fancy graphics - i.e., present problems solutions in a way that is different than the way they themselves think about it. This is a mistake that many other TED-style talks or cable TV documentaries about science make. These talks also include small tangents that could easily be the subject of other talks. You can learn a lot from seeking out and taking notes on good presentations.

Two presentations “close to home”

Here are two of my previous presentations:

Alvarez symposium (2011, immediately following my PhD) - this was a general audience (non materials scientists) and the purpose was to honor the late physicist Luis Alvarez. I’m clearly a bit nervous but have pretty good slides to lean on. This is also the first time a talk of mine was recorded and I learned a lot by watching it. http://bit.ly/2pWKiuW

University of Wisconsin summer school (2014, ~3 years past my PhD)- the audience were all materials scientists interested in learning modeling techniques. By now I am more comfortable in giving a talk and have corrected some of the errors of the previous talk. http://bit.ly/2pEflZm

Presentation checklist

Here is a checklist you can use to improve and verify various aspects of your presentation.

Easy things to do:

  • Number your slides. Numbered slides make it easy to refer to specific slides during the Q&A or feedback period.

  • Confirm all font sizes are large enough so that even people in the back of the room can read them. One good way to do this is to make the fonts way too big, then reduce the size until manageable (rather than starting too small and increasing from there, which in 90% cases leads to fonts that are still too small).

  • Write slide headings as snippets that contain useful information. A bad heading would be “Effect of +U parameter”. A good heading would be “Band gap and VBM d-character increase with +U parameter”. There is a style of slide called “evidence-assertion” that is generally very effective and should be used often.

  • Sharpen your images. Rescaling images in Powerpoint tends to make them appear soft, and projectors can also be less sharp than your display. Use “Format Picture->Corrections->Sharpen” to sharpen all your images and make them clearer for display.

  • Make sure you are not showing too many plots. The audience is seeing your plots for the first time. Any new plot you bring up will take at least a few minutes for the audience to digest. You need to explain the axes and give them time to understand the scale, you need to explain the various curves being plotted and how they relate to one another, and finally you need to explain the overall message of the plot. Because each plot should be a major chunk of time, you don’t have room for too many of them in most talks. One big mistake I see is that people want to keep their presentation to “10 slides”, but then they have 4 plots per slide.

Intermediate things to do:

  • Minimize the use of written text. Research demonstrates that your audience cannot read text on your slide and process what you are saying at the same time. Every second they are reading, they are not listening to you. In contrast, audiences have no trouble simultaneously listening and processing visual information (diagrams, images, etc.). Design your slides to account for this quirk.

  • Convey information through multiple “channels”. Ensure that critical information is not only contained in your speech/delivery but also through a visual channel (images or short text phrases / conclusions). People may not be able to hear you or might be distracted by their own thoughts for many moments in your presentation. Or, they might not understand a visual diagram and be helped by reiterating the point a different way through your dialogue. Having multiple channels maximizes the chance that they will receive the signal of your talk even when there is external “noise”. More advanced presenters will use body language or position as another “channel” through which to convey information.

  • Rehearse your talk for “flow”, “momentum”, and “energy” and cut slides that disrupt flow. Rehearse your talk, paying attention to the slides/sections in the talk where you are (i) struggling to explain a slide, (ii) where your energy / enthusiasm level drops, or (iii) the momentum of the talk seems to be slowing down. One symptom of such struggling is talking quickly in order to explain everything on the slide. 90% of the time, I find that removing such slides from the talk (i.e., moving it to an Appendix/supporting slides) is the best course of action even if I initially think that slide is important. Rehearsing the section again usually reveals you can maintain the energy and flow of your talk much better without the obstruction of having to explain that slide, and you can explain away the missing concept in a sentence or two while retaining the momentum of the previous slides. If it turns out the slide was in fact critical, then perhaps re-design the difficult slide as multiple slides to more gradually set up the concept.

  • Memorize the order of your slides; use “Slide sorter view” to help. During every point in delivering your presentation, you should be able to picture what the next slide in the presentation is. If you can do this, you are more likely to speak in a way that naturally connects between slides rather than abruptly stops/starts between slides. Some presenters use “presenter view” in Powerpoint during their talk to help with this, but I would say that depending on this feature is less likely to lead to smooth explanations than memorization. To mentally remember the order of slides, I stare at the slide deck in “Slide Sorter” view. The “Slide Sorter” view can usually show me most or all of the presentation at once since each slide is a small thumbnail, and I can easily see the visual overview of essentially the entire presentation. Thus, I can remember the visual arrangement of slides by studying the Slide Sorter view and can roughly flip through the presentation in my head.

Advanced things to do:

  • Video record yourself rehearsing the talk and watch yourself. Although you may find this uncomfortable or strange, you will learn much about your presentation style and areas to work on. Often, Anubhav will do this during your practice talk with him.

  • Connect your talk with the other talks in the session. You should modify your pre-rehearsed presentation based on the other talks in the session. You can move quickly through topics or introduction that have been covered a few times before and you can highlight how the other talks connect with your work.

  • Use an app like “Color Oracle” to see what key figures in your slides look like to color blind audience members. About 8% of the males in your audience likely have deuteranopia and having figures that account for this can be useful. There are color palettes for color blindness that one can find online, e.g., http://colorbrewer2.org. You likely won’t want to do this for all your slides, but might be worth it for showing key results.

  • Use an app like “Orai” to improve your vocal delivery. Orai will have you read sample text and analyze your speech for clarity, pacing, and emotion.

Miscellaneous advice

  • Make sure you clearly “sell the problem” before presenting your work and your solution. In many good talks, the problem is described in a way that the audience feels (i) that the problem is important and (ii) that they understand the problem well enough to start brainstorming their own solutions before you present your solution (something like a mystery novel). Note that this is different than a paper/written document that simply tries to convey information efficiently. In a presentation, it is useful to have some drama and create some audience engagement.

  • Some techniques to help give better presentations are:

    • add comparison points (e.g., 1 kilogram of this material can store enough energy to power a light bulb for 10 hours; or, the amount of computer time involved, if done on your laptop, would take 50 years)

    • use analogies, particularly when presenting to a non-specialist audience (i.e., the material soaks up lithium ions like a sponge)

See also: http://go.nature.com/2opiiQh . It is illustrated by Jorge Cham from PhDComics and is packed with good advice.

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