There’s a lot of talk about an information explosion. Petabytes, exabytes, zettabytes and so on. There are certainly a lot of ones and noughts being stored, and storage vendors are happily hyping that up into an information explosion. But information is what it’s not.
Information is the complement of uncertainty. Uncertainty is measurable, at least in principle, by Shannon’s entropy formula. If I have some degree of uncertainty about something, and if I receive a series of digital symbols which somehow reduces my uncertainty about it by some amount, then the digital symbols have exactly that amount of information content. There are plenty of books about this stuff – it even appears in Tomlinson 2000.
So, for any of these hoards of ones and noughts, we need to ask what uncertainties they can mitigate; in other words, what questions they can answer. While the quantities of ones and noughts have increased crazily, there’s little sign of a corresponding increase in the volume of questions that we want to answer. And even for the questions that we do want to answer, it’s not clear that the data that we’re storing is going to help very much.
Going back to Shannon, it seems as if most of these noughts and ones can do little, if anything, to reduce anybody’s actual uncertainty regarding anything that they’re bothered about. The information value of each one or nought is microscopically less than a bit. The ones and noughts are not bits of information; they’re just ones and noughts, unless they can answer a question for us.
So, the storage chaps are neatly tucking away their zillions of ones and noughts, but they certainly don’t amount to the claimed petabytes of information. Nothing like it. The information explosion is something that doesn’t just happen: it’s something that we will have to engineer, and the ones and noughts are just its low-grade fuel.
Tags: data, information explosion, petabyte, shannon
Indeed. When the member for West Dorset dropped all that paperwork in the bins in St. James Park, the sensationalist press said he was throwing away information. The more temperate press knew he was just discarding data. Maybe the red tops got it right. Within all that data, there was information.