Not for the first time, I was inspired by listening to the excellent The Studies Show podcast . In their 26 November edition, Tom Chivers and Stuart Ritchie introduced collider bias, which is a horrible statistical anomaly that can make it seem that a study shows something entirely different from reality. What's particularly worrying is that, as the podcast demonstrates, many scientists aren't aware of this potential issue. I had assumed collider bias would be something to do with the kind of huge statistical analysis necessary to interpret what's going on in a piece of equipment like the Large Hadron Collider at CERN - but in reality the 'collision' in question is simply down to the way a pair of arrows point to the same location on a kind of flow diagram. What this statistical anomaly can produce, though, is the kind of result we love to hear (and scientists love to find) - results that make you go 'Huh? That's surprising.' Examples given included that...

REVISIT SERIES -  Edited posts from February 2010 and March 2015 I've long marvelled at the success of the wonderfully unscientific concept of homeopathy. This is a double-length post pulling together two homeopathic adventures. Just over a week ago there was a mass overdose of medication sold by responsible companies like Boots. [I'm pleased to say, since this post, Boots has stopped making homeopathic remedies, though they currently still sell a handful of products.] Across the world people took vastly more than the recommended dose. And nothing happened. The reason? They were overdosing on homeopathic medicine. The campaign was known as 10:23. The strange numbering refers to  Avogadro's number . This is a number that delights chemists - it's the number of atoms in a mole of a substance. The actual number is around 6x10 23 , where 10 23 is 1 with 23 zeroes after it. The reason this is of relevence to homeopathic medicine becomes clear when you realize how these medic...