There it was again in the papers this morning: the falsehood that a Chinese purchasing managers index below 50 means China's manufacturing output is falling. The market has been told the story so many times, it probably believes it.
As previously reportedand is demonstrated by Chinese statistical releases monthly, a PMI a bit below 50 still results in China's industrial production growing by 8 or 9 per cent. Given the size of China's industrial production engine, that remains strong growth, just as the world's second-biggest economy growing by 7.6 per cent still represents strong growth.
Therein lies the disconnect between the more sanguine view of China regularly offered by the Reserve Bank - that China's rate of growth has calmed to a more sustainable level - and the headline-grabbing view of the general commentariat that China's growth rate has crashed and we'll all be rooned.
On current growth rates, China remains on track to overtake the US as the world's biggest economy in just five years on a purchasing power parity basis.
But it's not just the interpretation of statistics that can mislead markets. While we were sleeping on Friday night, there was some very strange trading going on in the moments after the release of Ben Bernanke's Jackson Hole speech.
The immediate market reaction was to wipe 100 points or so off Wall Street, but then it looks like someone actually read the speech and it wasn't so bad, the market turning on a dime and finishing up 100.
The question arises about how such a big movement, representing the winning and losing of many billions of dollars, could be justified on what would have to have been a prize effort by any speed-reading champion. The US Federal Reserve chairman didn't stray from his prepared text — all 4550 words of it. What sort of a man would you have to be to skim that so quickly as to make a 100-point market call? Or would you have to be a machine?
Out of somewhere near left field comes an American lawyer with the suspicion that it was the Borgs that wiped all that value off US shares in a few minutes, that the released speech was electronically scanned in a fraction of a second by computers operating off key words rather than genuine intelligence and then set off sell programs.
It might sound a little science fictional, but the story comes from a lawyer with a particular beef about the automated legal searches increasingly left to the machines. And the dangers of computerised trading, of turning over the market to machines playing at unfathomable speed and volume, are reported more than enough to make one wary.
Ralph Losey pushes a barrow for maintaining hybrid legal searches — applying human intelligence over the top of the computers. He might have the computer by the mouse tail. It doesn't seem very radical to hope that there is still some human intelligence being applied to market trading, as well as interpreting Chinese statistics.
Michael Pascoe is a BusinessDay contributing editor