Lies, Damn Lies, and Statistics

April 19, 2010

A saying often attributed to Mark Twain goes: “There are three kinds of lies: lies, damn lies, and statistics.” (Twain, interestingly, attributed the quote to Benjamin Disraeli.) I found myself wondering about the third variety of lie a few days ago as I watched a series (as opposed to a group) of pre-school-aged kids riding the Tokyo subways on their own, during the morning rush hour, no less. These four- and five-year-olds were engaged, for the most part, in more or less the same activities as their adult co-riders: listening to iPods, sleeping, or reading comic books (albeit of a slightly less graphic nature than the adult versions). From the lack of wonderment or excitement on their faces, it was clear that this was an everyday occurrence in their young lives. In the US, if you let your kids ride big-city subways without adult supervision, you would likely face charges of child neglect or endangerment, if not outright child abuse. So this got me to thinking: are kids really safer in Japan than in other places? Are Japanese parents lax in attending to the needs of their children? Or are Americans simply wildly paranoid nowadays, seeing danger where there is little or none? Surely there must be some statistics about this, right? Well, yes and no; it turns out there are a number of variables, not the least of which is different measurements of what constitutes child endangerment (see above example). Still, I was able to glean some interesting stats:

1)    It turns out that Sweden has the world’s lowest child-injury mortality rate, and Japan is well down that list with regards to the developed world, number 18, to be exact.

2)    There are some correlations to be drawn from this, as Japan has a higher incidence of drowning deaths, for instance, coupled with much deeper bathtubs than those used in Sweden; also, choking deaths are far more common in Japan, perhaps a result of dining tables being lower, thus providing easier access to curious youngsters; traffic deaths are rather more prevalent as well, perhaps because mothers often ride bicycles with one or two kids aboard, usually sans helmet.

3)    So, by most measures, it would seem that kids are no safer in Japan than in many other places, but still the parents, on the whole, are nowhere near as paranoid as their stateside counterparts. It seems that the statistics don’t hold them in thrall nearly to the degree that they do Westerners.

Another interesting use of statistics began in the late 1980s as promoters of safe sex (or in some cases, promoters of no sex at all) cited evidence of rising cases of HIV and AIDS worldwide, thereby attempting to influence a generation of young adults to adopt abstinence, monogamy and/or the use of condoms as disease preventatives. The truth of the matter, if you run the numbers, is that today there are fewer than 1,100,000 HIV-positive people in the US, according to the Center for Disease Control. If you accept the census figures that there are some 250,000,000 people in the US, then your chances are in the neighborhood of 1-in-250 that any potential sex partner might be a carrier. If you restrict your partners to non-gay and non-intravenous drug users, that number slides to fewer than 1-in-500. (In fact, only 13% of American men who are HIV-positive acquired the disease via sex.) So, although I am not suggesting or condoning this, the raw statistics indicate that you could merrily (and more or less randomly) engage in unprotected sex for the remainder of your natural life, with a statistically insignificant chance of a lethal outcome. This is a markedly different interpretation of the statistics than that offered by those with a more personal stake in the controversy.

Smoking? Here’s another example. While everyone agrees that smoking is a leading cause of lung cancer, and that 90% of people who die of lung cancer are current or ex-smokers, the numbers begin to get a bit hazy after that. A quote from webmd.com:

“A 51-year-old woman who smoked one pack per day for 28 years before quitting nine years earlier had a less than 1% chance of developing lung cancer in the next 10 years. But a 68-year-old man who has smoked two packs a day for 50 years and was still a smoker has a one in seven chance (15%) of getting lung cancer in the next decade.”

So basically, a guy who has smoked heavily for his entire adult life, and is still smoking, has a less than 15% chance of developing, let alone dying from, lung cancer! The cigarette companies should be trumpeting this statistic from the rooftops: “Smoke two packs a day for life, and you still have an 85% chance of never getting lung cancer!” Once again, I am not condoning smoking, nor am I a smoker myself. I just think that people with agendas to promote don’t necessarily have your best interests at heart, so I am simply suggesting crunching the numbers for yourself pretty much anytime somebody tries to use statistics on you to support their point of view, and see how your risk/reward tally balances out.

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