Feb 16, 2009

edward tufte and presenting data


I was lucky enough to attend a seminar from Edward Tufte, a couple of weeks ago, on the Presentation of Data and Information. Edward Tufte is probably best known for the book 'The Quantitative Display of Visual Information' and was an engaging and entertaining presenter. He has a very different style from the normal Powerpoint-driven presentation approach. In fact, much of his work is railing against the uses and abuses of Powerpoint and similar slide techniques.

The main take-away I got from the whole day was that if you have to communicate complicated data sets or information, that you really need to consider how people will use and interact with the data first. Too often, we go straight to presentation software and start trying to work out how to express the information in slides, rather than taking the time to consider if there are other, better ways to impart the information. Tufte was very keen on the concept of a 'super-graphic' which is a data rich, high resolution physical handout that lets participants see and consider a lot of data at once. A map is a great example of a super-graphic, or the weather page in a typical newspaper. A key part of this is that paper is much higher resolution than a typical computer screen (72dpi to 600dpi means you can show a whole lot more data in the same space). This is why multiple display screens are really useful for serious work. It also means that printing out and sharing data is a great way to get information infront of people in a meeting, rather than drip feeding it from slides)

I compare this idea to another guide I saw in the same week on creating powerpoint presentations that admonishes that there should never be more than 8 numbers on any slide or graphic. Tufte's response to this was repeatedly 'when did we become so stupid, just because we walked into a business meeting?' People handle large, complex data displays every day in the real world. People read and study sports scores in a newspaper, or financial reports without any trouble at all.

Let the data drive the presentation format, rather than the presentation software drive how the data is displayed.

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stop & search

a cold day in London

One of the least enjoyable experiences on a recent trip to London, last week, happened while I was taking pictures of the London eye. I was standing a few hundred meters away, shooting with a normal point and shoot camera, just like all the people around me, when a couple of police officers approached me. I'd heard about photographers being hassled in London but was surprised this managed to happen to me within 48 hours of arriving in the city. They started out by saying that 'they didn't really believe I was a terrorist, but were stopping photographers to make people aware that they were watching what was going on'. From there, they handed me a form that listed my rights under section s44 of the anti-terrorism law then proceeded to question me about what I was doing, where I was from, why I was taking pictures.

As far as I can tell, even though they themselves said they have no reasonable clause, the Terrorism act says that's fine. We spent about 5 minutes going through where I've lived and having me justify why I take pictures. Then they wanted to see all the pictures I'd been taking (again, as far as I can tell, in contradiction of their own guidelines on collection of evidence). On looking through the images, one of the officers stated that 'those look just like the sorts of pictures a terrorist would take' and then told me to move on. The picture above is what I was taking, when the stopped me. I got a 'stop and search' form listing that the stop was authorised under the anti-terrorism laws and that was part of a 'pre-planned op'. I can only assume from that they the London police have decided to institutionalise harassing photographers for the sake of   security theatre. Particularly, if when they find images that they think would be typical terrorist images, they wave the photographer on.

This is all in a city that seems to have more CCTV cameras everywhere than there are people. I'm not quite sure who if anyone is actually watching these camera feeds. The whole thing is quite worrying, for someone who has been out of the UK for a few years. We used to make jokes about books like 1984 or movies like V for Vendetta but it seems that piece by piece typical rights to privacy are being whittled away by a government that is using good intentions to grab as much additional powers as possible. Sure, it is just hassling a photographer in the street, taking pictures of a tourist attraction for no reason, but each time has an increasing chilling effect on what people feel they can do and what government authorities can get away with doing. I didn't argue with the particular officers, mainly as I didn't want to spend half my day discussing it in a police station on my holiday. Maybe that's part of the problem too.

'There's an implicit admission that Section 44 stops and searches do not detect terrorists. This is borne out by the available data. In the financial years 2003/4 to 2006/7, the Met stopped and searched 31,797 pedestrians using the powers of Section 44(2); of these only 79 were arrested in connection with terrorism - less than a quarter of a percent - and even fewer will be convicted. The purpose of deterring is feeble considering the extent to which the Home Office is ready to go to avoid revealing when and where the exceptional powers for Section 44 apply.'

At the end of this five minute waste of time, they started asking me about the number of megapixels my camera had, commented on how impressed they were by the quality of the pictures on the screen and asked where they could buy one and if I'd recommend it.

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