Society - More Statistical Bullshit

Among the top headlines today is a report by the BBC that 94% of banknotes in Spain have residues of cocaine on them. The story suggests that not all of those bills were used for snorting, but that residues may have come from contact with other banknotes.

Now, how did the un-named “experts” in the article come to this sweeping generalization about the approximate one billion banknotes in Spain? They sampled 100 bills. 100 out of a billion. That's 0.00001% .

Further, they sampled 20 bills from each of 5 cities. The cities and their populations are:

Barcelona 1,600,000

Bilbao 350,000

Madrid 3,000,000

Valencia 735,000

Seville 695,000

________

Total: 6,380,000

That’s 6,380,000 out of a population of 40,000,000. 16%. They sampled 0.00001% of the banknotes in the country focusing on 5 urban centers which comprise 16% of the population, not taking into account any of the rural communities. And somehow that is considered hard research worthy of international headlines.

Granted, I’m no statistician. And perhaps the nuances of the science escape me. But that sounds like a lot of bullshit to me.