Pretty much the whole of the online public speaking advice community has spent the last months (years?!) banging on about less text. Few bullet points with fewer words! Images are the way forward!
For people with data to show this has sometimes been a little bit scary (if my inbox and the questions I get on our presentations training is anything to go by).
My response is usually to suggest that people stand by the ‘less is more’ philosophy and think about graphical representation of their images. The inevitable then happens – the wrong kind of graphics, badly drawn…….. :) There’s some good advice kicking around in various places online but a lot of it assumes that people know quite a bit about statistical/graphical manipulation. So here’s my attempt to simplify things……
If in doubt, don’t. There’s nothing sillier than an un-necessary graphic on the screen. I’ve blogged about ducks and golden ducks in presentations before and I stand by that advice: do you really (and I mean really!) need a pie chart to show what percentage of the population are male? If so, take a long, hard look at your approach and your audience! :) Sometimes a lot of things can be simply said – you don’t need a graph of any kind.
If you’re trying to show a change over time, it’s almost always best to stick to the most simple of structures – a two dimentional graph. Put time along the X (horizontal) axis, from left to right, with the ‘most future’ date on the right hand side. Put whatever you’re commenting on as changing over time on the Y (vertical) axis. That’s it. Keep it simple. Don’t try and show too many things at once – I’ve rarely seen an on-screen graph that could be read by an audience that had more than a couple of variables (other than time).
Remember a couple of simple statisical rules too. Only use lines if it’s justified by your data! If you know the number of unemployed in January and July, don’t be tempted to use any kind of lines for your graph which imply you know the number of unemployed people in the months between. Put simply, that’s a kind of lie. For all you know, the number could have gone up in February by tenfold and then spent March to June coming down to July’s level, not going up in a smooth line from Jan to July!
If you’re using something like Excel to draw your graphs and things, remember that it will do its best to sabotage your graph by picking colours which don’t project well by default and lines which are hopelessly thin, when looked at from the back of the room!
If you’re trying to compare two variables, neither of which is time, the same kind of graph (such as in a scatter plot) is probably the best way to go. If you’re trying to show more than two variables at a time, be very, very careful. My instinct is that if you’re trying to do that, you’re trying to do too much at a time, to be honest. If you must do it, show the relationships between your variables seperately first.
All the research I’ve read suggests that data are best passed on to your audience in handouts in any case. Data should be printed – your presentation should concentration on the trends in the data and in interpreting the data.
Simple!
