Think about it: at what point did you realise your ex was an idiot? Significantly later than your friends did, right? All that time you could have been using Tinder to travel the world, improving your casual sex life, and learning how to slide into Instagram models’ DM’s, yet you persisted with someone who watched Game Of Thrones without you and was as committed as a polygamous nomad.
Why? Though your kinder friends will put it down to you also being an idiot, scientists now have a more sophisticated explanation, thanks to a recent study on the age-old “sunk cost fallacy”. What is the “sunk cost fallacy”? Basically, in the same way that you wait in a slow line at the grocery store, or continue taking a class you already paid for but hate, people often stick out tedious relationships—because of the time and energy invested they will never get back.
If that psycho-evolutionary flaw doesn’t sting enough, last week’s study found that we share this trait with mice and rats, “New research has discovered that humans are not the only species that share these economically irrational flaws,” (Science Daily).
“The key to this research was that all three species learned to play the same economic game,” said Brian Sweis, the paper’s lead author, an MD/PhD student at the University of Minnesota.
Essentially, mice and rats had a limited amount of time to search for flavoured food pieces, while humans spent a similarly limited time-budget “foraging” for entertaining videos on the web. As reported by Science Daily, “Rats and mice ran around a maze that contained four food-delivery-locations (‘restaurants’). On entry into each restaurant, the animal was informed of how long it would be before food would be delivered by an auditory tone. They had one hour to gather food and thus each entry meant they had to answer a question like, ‘Am I willing to spend 20 seconds from my time budget waiting for my cherry-flavored food pellet?’ with a delay lasting anywhere from 1 to 30 seconds.”
Similarly, “Humans saw a series of web galleries and were informed of the delay by a download bar. This meant humans had to answer an equivalent question: ‘Am I willing to spend 20 seconds from my time budget waiting for my kitten video?’ In this way, each subject from each species revealed their own subjective preferences for individual food flavours or video galleries” (SD).
In the experiment, each entry required two decisions, one when the delay was revealed, but did not count down, the next (if the initial offer was accepted) when subjects could quit and change their minds during the countdown. Unfortunately for those who like to think humans are intelligent, the authors found that all three species become more reluctant to quit the longer they waited—demonstrating the sunk cost fallacy.
“These tasks reveal complex decision processes underlying the conflict between really wanting something on the one hand versus knowing better on the other,” said Brian Sweis, one of the authors of the paper. “This is a conflict between different neural decision systems, and that means we can separately manipulate those systems,” said David Redish, another of the authors.
So if you have to get the “sunk cost fallacy” out of your system, take it out on an all you can eat buffet, but when it comes to your dating life—avoid it like a raisin cookie.