When you get a lot of smart and interested people together to make a prediction in aggregate, it can be scary accurate. Anyone who has read the James Surowiecki business science classic The Wisdom of Crowds, and a host of corroborating authors such as Malcolm Gladwell, knows that.

So what if you applied that brave new world of expert prediction markets, of crowdsourcing the future, to the Facebook IPO?

That’s what famed investor Chris Sacca wondered aloud on Twitter, and programmer James Proud endeavored to find out. And thus was born Facebookipodayclosingprice.com, Proud even buying the exact URL Sacca had idly requested Tuesday.

By end of day Thursday, it had garnered more than 1,400 predictions, mostly from the Valley’s top luminaries — entrepreneurs, investors, analysts and others who know a thing or two from IPOs. And it was getting up to 20 visitors every second.

Pollsters and prediction market experts will tell you you need more than a thousand inputs for a good aggregate result with a low margin of error. So what did this prediction market come up with? And could you — or Sacca — get very rich in one day by banking on the result?

In theory, yes. Facebook’s launch price Friday morning will be $38. This site is predicting, in aggregate, that the stock will hit $54 by close of market Friday, for a total valuation of $135.7 billion.

Buy enough shares, and that $16 difference would make for a tidy one-day profit.

Of course, prediction markets have never been tested in this kind of circumstance. IPOs are inherently nerve-wracking wild rides. The Twitterati have been known to be wrong before. We certainly won’t be opening our wallets on the basis of this prediction.

But we will be eager to check back in at the closing bell, 4pm ET Friday, to see how close the prediction market came. Join us then!

More About: chris sacca, Facebook, facebook ipo, prediction market, trending, Twitter

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