I love reading interesting predictions. Anyone can make safe short-odds claims, but I'd take a handful of unusual and correct pot-shots over stating the bleeding obvious any day. (Or perhaps what is the bleeding obvious for some well-informed commentators may be an unusual pot-shot to myopic ol' me.) Accordingly, while we've played prediction games in the past - Iain's even run a couple, though rather intricate ones - there is often a tendency for the games to reward conservatism and selection of relatively likely options. There are things you can do with scoring systems, but they don't make the underlying prediction targets more interesting. I would be more entertained by a prediction game dealing with plausible long-shots - ideally ones where players make the plausible long-shot predictions, but a cunning mechanic would be required to ensure, er, length of shot.
This is not quite that game. This is an attempt to see whether my Friends list can produce a prediction market worth a damn by trying to form a consensus opinion of just how unlikely some moderately unlikely events are.
Below, please find twelve moderately unlikely events, all of which would be slightly surprising, hopefully none of which are completely implausible. Unless otherwise stated, I am interested in whether they might happen after July 31st, 2008 and before February 1st, 2009, excluding these boundary dates, considering local time zones as appropriate. Hopefully these are moderately international, or at least skewed towards the predicted audience.
* Oil to trade at $200/barrel or higher.
(Any of Brent crude, New York light sweet crude or West Texas Intermediate crude, which are trading at around $143.)
* BBC Global 30 stock market index to drop below 4750.
(It is currently valued at 5230 and was based at 5000 in September 2004.)
* John McCain to win at least 336 Electoral College seats in the 2008 US Presidential election.
(George Bush won 286 Electoral College seats in the 2004 US election.)
* Gordon Brown to stop being Prime Minister of the UK, Labour Party leader or both.
* The USA to win at least one more gold medal than any other single country at the Beijing Olympics.
(At the 2004 Olympic Games, the USA won four more gold medals than second-placed China.)
* The New England Patriots to win Super Bowl XLIII, expected to take place on or around February 1, 2009.
(They won their first 18 matches in the previous NFL campaign, only to lose Superbowl XLII. See also the so-called Super Bowl curse.)
* Microsoft to make a takeover bid for (or merger bid with) Yahoo that Yahoo's board of directors accept or recommend acceptance.
* Firefox usage to reach 33% or higher.
(Source: any month or any quarter reported by W3 Counter global stats, TheCounter global stats or Net Applications stats. See recent stats for comparison.)
* The Harry Potter and the Half-Blood Prince movie, i.e. Harry Potter 6, to gross at least $285,000,000 at the US box office by (and including) the weekend concluding Sunday February 1st, 2009.
(Counterpart figures for the previous five Harry Potter movies.)
* One or more of Prince William, Prince Harry, Princess Beatrice and Princess Eugenie to marry publicly.
* USA and/or Israel to execute an overt air strike against Iran.
* There will be no more than two major hurricanes (category 3+) in the 2008 Atlantic Hurricane season.
(Current predictions are for two to five.)
My questions: how many of these will occur? Which are most likely? Which are least likely?
Formally, let's incentivise you to predict rationally through a scoring system whose incentives are hopefully not too skewed. Please predict how many of these twelve events will happen; earn 10 points for being exactly correct, 9 points for being incorrect by one in either direction, 8 points for being incorrect by two in either direction and so on. Please select which four of the twelve are most likely to occur; putting my Bayesian spectacles on and conflating probability with results from single trials, three bonus points will be awarded for each of your "most likely to occur" selections that do occur. Please select which four of the twelve are least likely to occur; two points will be deducted for each of your "least likely to occur" selections that do occur.
Also, shout up if it is not clear how any of these will be assessed. Should you spot a reasonable way in which any of these possibilities could be described as being neither true nor false, or where it is not clear how the claims of truth or falsehood will be authenticated, please comment sooner rather than later. You can safely assume that I am prepared to interpret these moderately liberally - or, at least, that I am unlikely to be swayed by pedantry. On the other hand, if what you consider an important distinction that I may not have taken into account is what you fear I consider pedantry, I will appreciate it if people quibble early rather than waiting to see if it'll make a difference in the scoring.
Predictions are visible to all and can be changed up until the point at which I close the poll. The closing date and time will depend on my real-life demands, but I intend it to be before I go to bed after my day shift on Tuesday 8th July.
How many of the twelve events will occur?
Which events are the four most likely to occur?
Which events are the four least likely to occur?