The stupidest statistic you’ll see this week

Godzilla failed in his apparent goal (at least in the first movie) to crush all the people of Japan under his big reptilian foot. But what the radiation-blasting monster couldn't achieve by brute force, the Japanese may themselves bring about by their own habits of reproduction—or lack thereof.

A new study from a group at Tohoku University Graduate School looks at the low and falling birthrate in Japan and calculates how it will affect the country in the future. The findings, as recounted by the Japan Times, are not joy-inspiring, if you want Japan to continue existing as a nation.

The number of children under age 15 went down from 16.9 million in 2011 to 16.6 million in 2012, and is decreasing by one every 100 seconds, on average. At this rate, the very last child in Japanese history will turn 15 on May 18, 3011—and that's it. No children again, ever, at all. The Japanese of the 31st century will just continue to get older and age and die, unless of course no one is aging and dying in the 31st century, which could certainly be possible, for all we know.

Just to point out something that may be obvious: this would-be statistic is meaningless. The idea that you could predict the birthrate 1,000 years is flat-out bullshit. I don't even think you could predict the birthrate in 100 years, let alone 10 times that.

Do the researchers really believe this figure? Do they think they can calculate the exact date 1,000 years in the future when the last child will graduate to young-adulthood?

I'm going to assume that they don't really believe that, if only for my own faith in our species. I presume they're just making a point about how Japan's birthrate is quite low and getting lower (which was well-known long before this; see graph above), and this was just a sexy (perhaps an ill-fitting word here) way of depicting it. That would explain why they posted a real-time child-population calculator on the university website, which they say they will re-calibrate each year.

Which is all well and good. But it aggressively clashes with the mindset of science, which has some powerful ideas to quantify how much we don't know like uncertainty, error bars, and significant figures. Picking the date when the last Japanese child will hit age 15 is like glancing at a picture of a faraway beach and then guessing exactly how many grains of sand there are on it.

So don't pretend, or believe, that it actually means anything.

Image: Wikimedia Commons