In the words of the creator of this graphic, the point here is that “there is no pattern”. The YouGov pollsters seemed to be a little more accurate, but then, as was also pointed out by the graphic’s creator, they only had one year to give it a go. Low N on that group, but maybe we can call them ‘one to watch’.
There is always a tendency in science – bench science, social science, any kind of science – to show positive results. It sort of sounds like: “Look! I found something!” Or, more likely, “After controlling for everything I could think of, including maternal grandmother’s underwear size, I have found a statistically significant correlation in the predicted direction.” But there is almost no support for saying, more or less, “I was looking for something but I found nothing.” In this particular case, a non-finding is of interest because it suggests action. We can stop paying attention to prediction polls (or chance it and continue to pay attention to YouGov, with a grain of salt). What works best here is the rigorous reporting of no pattern. Multiple polling companies, multiple elections, still no pattern.
What needs work
Seriously needs a key. Red and blue are always political colors, yellow not necessarily so, and the meanings of each cannot be assumed.
Love the title ‘poll dancing’ but wish it would mention ‘UK’ and ‘elections’ somewhere. We can deduce from the listing of the Guardian as a source that it probably has something to do with the UK, but information is global now, and we cannot assume national origins anymore. I often make this mistake myself, easy to forget to mention the nation-state. The good news is that our audiences are no longer only our neighbors. Or at least that’s how I like to think of it.
Momin, a young fellow who contacted me by email suggested I post this one.
McCandless, David and Key, James. (2010) “Poll Dancing: How accurate are poll predictions?” from Information is Beautiful.
McCandless, David. (2010, May 6) General election 2010: Information is Beautiful goes poll dancing at The Guardian, Data Blog.