The secret of learning is to be wrong 15pc of the time

BEING wrong 15 per cent of the time is the secret to learning new things, scientists have found.

Academics have long suspected that people learn better when they are challenged to grasp something just outside of their existing knowledge.

Make a task too hard and participants will give up without acquiring any new skills, but if it is too easy, they will also not pick up anything useful.

But that “sweet spot” has always been unknown.

To find out where it lies, researchers at the University of Arizona conducted a series of machine-learning experiments in which they taught computers simple tasks, such as picking whether a number was odd or even.

They found the computers learnt fastest in situations in which the difficulty was such that they responded with 85 per cent accuracy.

“These ideas that were out there in the education field – that there is this ‘zone of proximal difficulty’ in which you ought to be maximising your learning – we’ve put that on a mathematical footing,” said Prof Robert Wilson

“If you have an error rate of 15 per cent or accuracy of 85 per cent, you are always maximising your rate of learning in these two-choice tasks.

“If I give really easy examples, you get 100 per cent right all the time and there’s nothing left to learn.

“If I give really hard examples, you’ll be 50 per cent correct and still not learning anything new, whereas if I give you something in between, you can be at this sweet spot where you are getting the most information from each particular example.”

The academic team, which included researchers from Brown University, the University of California, Los Angeles and Princeton, have dubbed it “The 85 per cent rule” and say it could help teachers pitch their classes at the right level.

The research was published in the journal Nature Communications.