Playing Dumb on Climate Change?
According to Naomi Oreskes:
95 percent might have made some sense back in Fisher's day. After all, it was very difficult to test 20 hypotheses at once back then. Today, it's possible to automatically devise hundreds or thousands of hypotheses and data dredge to verify them.
Where does this severe standard come from? The 95 percent confidence level is generally credited to the British statistician R. A. Fisher, who was interested in the problem of how to be sure an observed effect of an experiment was not just the result of chance. While there have been enormous arguments among statisticians about what a 95 percent confidence level really means, working scientists routinely use it.
But the 95 percent level has no actual basis in nature. It is a convention, a value judgment.
The above applies more strongly to hysterical hypotheses about the consequences of global warming than to hypotheses about global warming itself. It's hard to come up with a few zillion hypotheses about one time series.
But wait, there's more:
[Insisting on a 95% confidence level] makes sense in a court of law, where we presume innocence to protect ourselves from government tyranny and overzealous prosecutors—but there are no doubt prosecutors who would argue for a lower standard to protect society from crime.I think we do have to protect ourselves from government tyranny and overzealous EPA regulators.