Wednesday, August 13, 2008

You will only remember 10% of this, apparently

Every now and again you see a claim that we remember 10% of what we read, 20% of what we see, 30% of what we do... I forgot how it goes, and so I should since it is entirely spurious. In one place, I found it reported with much more plausible precision: 9%, 17.5%, 31%, etc. But it was still rubbish, it turns out. Some years ago I saw this stated authoritatively on a BBC web page, even attributing it to 'recent research', so I wrote to ask for the citation. They replied that they had got it from the British Dyslexia Association, so I wrote to them. They in turn replied that they had read it somewhere, but they hadn't got a source. 

Hunting for the source, I posted a query on the Infodesign Cafe, which put me in touch with Michael Molenda of Indiana University, who was on a similar hunt. He eventually published a short paper with his findings (you can find it here). He traced it to Edgar Dale's 'cone of experience', published in the late 40s. Dale used a schematic diagram (below) to illustrate his view that increasing richness of experience would lead to greater learning. 


Somewhere along the way, someone has added the figures, and these have been repeated endlessly ever since, deeply embedded in the teacher training curriculum. Tony Betrus and Al Januszewski of the State University of New York have published a collection of bad cones

It seems unlikely that a 'quotation' like this would have survived for so long unless there is some truth in it - in other words, it chimes with people's experience in some way, just as a saying such as 'a picture is worth a thousand words' does. Perhaps this is just a modern version of a proverb – it's just that these days we need statistics. 

The Education department at Cisco Systems have looked into the evidence that actually does exist, and produced a useful metareview .