In a comment on Cath’s blog the other day, she mentioned the Baader-Meinhof phenomenon. Though I’d not heard of Baader-Meinhof before, the context of the comment made it clear that it is a phenomenon that I’ve noticed, but never realized had a name. Also known as the “frequency illusion”, the Baader-Meinhof phenomenon is:
“the illusion in which a word, a name or other thing that has recently come to one’s attention suddenly seems to appear with improbable frequency shortly afterwards” (Source: Wikipedia)
Looking this up on Wikipedia to confirm that it is what I thought it was1 led me to a list of all sorts of cognitive biases. Cognitive biases are basically common errors in thinking. The one I’m most familiar with is confirmation bias – the tendency humans have to pay attention to things that confirm what we already believe and ignore things that challenge what we believe. But this list on Wikipedia introduced me to tonnes of new and interesting ways in which our thinking tends to be biased.
- Belief bias – tendency to believe that someone’s argument is correct because the conclusion is believable.
- Endowment effect ((Not what I thought it was going to be about when I first read the name.)) – tendency of people to expect more to give up an object than they’d be willing to pay to get that same object2.
- Forer effect or Barnum effect – tendency of people to believe that a description that is supposedly of them is a good fit, despite the fact that it is so generic, it could fit anyone. The obvious example is horoscopes.
- Gambler’s fallacy – tendency to think that what’s happened in the past can affect the probability of a future event when the past event actually has no effect on the probability of the future event. For example, if you flip a coin, you have a 50% chance of it turning up as “heads”. Each subsequent flip of the coin also has a 50% chance of turning up “heads”, but if you flip 5 heads in a row, you’ll tend to feel like there’s a higher chance of it coming up “tails” since it’s come up “heads” so many times.In reality, of course, that next coin flip is still 50-50.
- Illusion-of-truth effect – tendency believe something to be true if we’ve heard it before3.
- Irrational escalation – tendency to justify continuing to invest more into a decision because you’ve already investment a bunch, even when you get information that it’s a bad decision and you should really cut your losses4.
- Observation selection bias – tendency to assume that the frequency of something happening has increased when it hasn’t increased in frequency, simply because you started paying attention to the thing.
- Rhyme as reason effect – tendency to believe something to be true because it rhymes ((Don’t be rash, give Beth some cash!)).
Of course, I’m sure that know that I know of it, I’ll hear people talking about the Baader-Meinhof phenomenon everywhere!