So, Freakonomics (Steve Levitt, Chicago, and journalist Stephen Dubner) blogged and tweeted about my "It's the weather, stupid ..." paper (gated version, ungated version).  Their book sold 4,000,000 copies and their daily tweets alone reach +500,000 followers ...

It's the Weather, Stupid: New evidence from Denmark’s annual May Day demonstrations on the power of the weather. bit.ly/YHDYEF
— freakonomics (@freakonomics) May 9, 2013

BTW: So did my old friend, Lars Christensen at Market Monetarist.
Here and here are

I have tried to do a bit of "forecasting" with my model for turn-out at May Day demonstrations (based in my "Public Choice" article "It's the weather, stupid! Individual participation in collective May Day demonstrations").  A simplified model including

• Average of min./max. temperatures (according to DMI's weather forecast, as of Friday, for Tuesday min. 6 degrees Celsius, max. 18 degrees = average 12 degrees)
• Bandwagon (last year's no. of participants = 55,000)
• Colour of government (not a "bourgeois" government, i.e. a dummy = 0)
• Post-Soviet collapse (dummy = 1)

Using these four variables, we get a forecast of 81,782 demonstrators in Copenhagen's Fælledparken (standard error of estimate: 42,000).  Using

Som jeg tidligere har omtalt, har jeg beskæftiget mig med at teste nogle klassiske modeller af på et originalt dansk emne: Hvad er det, der påvirker, hvor mange der deltager i 1. maj demonstrationer?  Artiklen er nu færdig og udgivet i Public Choice, hvor den vil kunne læses af folk, der har net-adgang via et bibliotek eller et universitet.  Her er sammendraget:

"We investigate the possible explanations for variations in aggregate levels of participation in large-scale political demonstrations. A simple public choice inspired model is applied to data derived from the annual May Day demonstrations of the Danish labor movement and socialist parties taking place in Copenhagen in the period 1980–2011. The most important explanatory variables are variations in the weather conditions and consumer confidence, while political and socio-economic conditions exhibit no robust effects. As such accidental or non-political factors may be much more important for collective political action than usually acknowledged and possibly make changes in aggregate levels of political support seem erratic and unpredictable."

En mere "populær" version optrådte for to år siden som kronik i Berlingske. På min gamle blog har redacteuren, den gode Christian Bjørnskov, været så flink at give den et par venlige ord med.