The previous post took a swipe at applying statistics/probability in the social/biological sciences, but it occurs to me that the physical sciences are by no means immune from the temptation either. In astronomy, the Drake equation (which involves several terms that must be assigned values) was a famous attempt to guesstimate the chances of 'intelligent life' existing elsewhere in the Universe. Now, I have no doubt, based on nothing more than common-sense inference, that intelligent life exists elsewhere in the Universe (or in the Multiverse, as the case may be), but I do doubt that it can be demonstrated empirically with applied statistics. [Correction: the Drake equation applies only to the Milky Way galaxy, NOT the entire Universe, let alone any Multiverse -- the same underlying problems still arise on the 'smaller' scale though.] And while not a huge fan of Michael Crichton, I largely agree with his words on this one:
"The problem, of course, is that none of the terms can be known, and most cannot even be estimated. The only way to work the equation is to fill in with guesses... As a result, the Drake equation can have any value from "billions and billions" to zero. An expression that can mean anything means nothing. Speaking precisely, the Drake equation is literally meaningless…"
(again though, I'd substitute the word "silly" for "meaningless")
Somewhat interestingly (for its analogousness to the Ivory-bill situation) there is actually a second-take on the extraterrestrial life debate, known as the "Fermi paradox," which tries to argue against the probability of intelligent life elsewhere (because, hey, wouldn't we have found them by now?).
On a complete side note, while I'm not always a fan of statistics applications, I am a big fan of good nature writing, and If Julie Zickefoose isn't the best nature wordsmith living in America today I don't know who is. Her latest book, "The Bluebird Effect" will soon show up in bookstores, so I'll put in a plug for it.
And while at it, I've pointed readers to her 1999 essay on the IBWO (pre-Arkansas hoopla) from "Bird Watchers Digest" multiple times before and will do so again:
http://www.juliezickefoose.com/articles/ivory_billed_wp.html
-----------------------------------------------------------