Georg Hoffmann of PrimaKlima has turned away from climatology for a moment to carry out an interesting statistical analysis of the Iranian election results. Bizarrely, the percentage split between the incumbent and the closest rival remained entirely stable throughout the count – an R2 value of 0.999. But even more bizarrely, the lead for Ahmadinejad doesn’t correlate with anything – as if the uniform national swing beloved of psephologists was real, or for that matter, as if someone had simply shifted the numbers across the board. For comparison, he ran the same exercise for the 2005 German elections, which shows a wide scatter of points with a concentration of big CDU leads in the south.
Then, however, comes the genuinely scientific bit. What would Benford’s law, the principle that in most data sets there is a large excess of numbers that begin with low digits, and that therefore fake data can be identified by its divergence from this, make of it? (The data, by the way, is available here.) Well…it turns out that the results pass the Benford test, which may mean that they are honest or possibly that the Iranian Ministry of the Interior reads blogs, too.