kip/bot/blog

Fun interview by Dan Rather of fivethirtyeight’s Nate Silver:

Some interesting things to note:

There’s a weird thing going on in this discussion about stats and polling where some very simple math is being turned into high science. If you spend a little time looking at Baseball Prospectus, it’s all algebra. There may be some underlying techniques in the crunching of the numbers, like regression, but the formulas are pretty simple. fivethirtyeight is largely a question of weighting polls, based on some historical data. It’s just not that complicated. Silver’s dissection of the GWU/Battleground poll is barely even a dissection — he just looked at the methodology and saw that they over-indexed older voters! I’m starting to find it frightening how innumerate people are . . . or is it how illogical they are given that it’s middle school math level?

As part of my poll-obsessing, I finally checked out fivethirtyeight, recommended to me by Alex. Short version is that Nate Silver, the author of the site, is also a leader of Baseball Prospectus. He is credited with creating the very powerful PECOTA system, which rethinks baseball statistics — mostly through pure intelligence, but there is some math that exceeds the AD&D level — and in the process creates a much better explanatory and predictive tool. (It also played no small part in helping to create fantasy baseball’s popularity and even help baseball make a comeback when people thought the fast-paced, pre-felonious NBA was going to surpass America’s pastime.)

fivethirtyeight is, and I don’t think this is oversimplifying, doing for political polling what it did for baseball stats: finding truths by refining, critiquing, and improving simplistic polling data. Today’s post on the site was one of those aha moments:

I have gotten an increasing number of questions about the GWU/Battleground Poll, which presently gives John McCain a 2-point national lead, even as essentially every other current national poll shows Barack Obama with a lead of at least 5 points.

Just because a poll is an outlier doesn’t necessarily mean that it’s doing something wrong. Pollsters may have legitimate reasons for having a different perspective on the election, and they may also occasionally produce odd results due to chance alone.

In this case, however, the poll seems to be making a relatively fundamental mistake: it is not weighting by age.

For months, I’ve been wondering why the hell some polls have been reporting a neck and neck race, while others show Obama steadily gaining ground. (Even stranger, why on earth is the always admirable John McCain pulling such silly stunts, throwing hail Marys, if it’s a dead heat?) Finally, someone explains it, and oh how bizarrely simple it turns out to be.

For those who are curious, here’s the weighting of the battleground poll in question:

18-34 17%
35-44 12%
45-64 40%
65+ 31%

Compared to the US Census/2004 election data:

18-34 26%
35-44 17%
45-64 38%
65+ 19%

Pretty clear. This poll massively overrepresents older voters who, at a local polling level, have been averse to Obama for a variety of reasons, and massively underrepresent the younger voters who Obama has targeted in campaign activities and who are likely to respond to the post Baby-boomer voice he’s cultivated.

So simple, no math. Can’t tell if I’m impressed at the baseball-stats freaks or disgusted at the innumeracy of the media, or even literate newspaper reading people.

Just kindle-bought Bob Neyer’s Big Book of Baseball Legends, and am amused by Bill James’s prologue:

The academics have won. The standards of accuracy that began in academia have been embraced by paid reporters and have now spread to the limitless legions of dignified researchers, pouding out accurate if boring biographies about absent and long-dead heroes.

And I’m not saying that’s a bad thing, you know? Dinosaurs are more interesting than unicorns. I don’t even read fiction; history is always more interesting. I am just saying… something humanizing and indefinable has been lost in the search for the truth — lost or, worse yet, thrown away. For thousands of years, men made slightly heroic fiction out of their own petty lives. You can’t get away with that anymore.”

It’s a strange introduction to a book that is largely about debunking baseball myths. Stranger still, coming from someone who almost single-handedly turned number-crunching into part of America’s pastime and may have done more for increasing overall numeracy in the country than any government initiative. Still, it’s nice to hear a high priest of truth-by-numbers acknowledge that there’s more to baseball, and other things, than the numbers might be able to tell.