Mea Culpa – Setting the Record Straight on Dale’s Cone/Pyramid

I have often leveled with friends that I could never run for political office. The reason is simple.

There are simply too many skeletons in the closet.

Last week I added one in our post relating deliberate practice to the educational setting. It involved this, our final image in the post:

What makes this a true mea culpa is that when Stephen Downes at Stephen’s Web linked to our article, we were at first surprised by his raising issue with our choice of the image. Having done some homework, we now say thankfully that our mistake did not cause Stephen to cast our piece to the blog scrap heap.

Debunking a Great Myth
The visual included what has come to be called the “Bastardization of Dale’s Cone.” The diagram actually melded several concepts together but two that should never have been, because the concepts do not pass research muster.

It involved one of the longstanding assertions regarding learning processes, that “people remember 10% of what they read, 20% of what they see, etc.” It seems that these numbers, presented to educators for the better part of 40 years, are not backed by research.

Will Thalheimer, PhD, President, Work-Learning Research, Inc., traces the first publication of the numerical assertions to D. G. Treichler of Mobil Oil Company. Treichler used the numbers in a 1967 article in the magazine Film and Audio-Visual Communications. According to Thalheimer, no citations for the numbers were ever provided.

Thalheimer goes on to note that Michael Molenda, a professor at Indiana University, is working diligently “to track down the origination of the bogus numbers.” His work lends some credence to the notion may have been developed as early as the 1940’s by Paul John Phillips of the University of Texas at Austin. Philips has a history of having developed training classes for the petroleum industry.

The bottom line is that these percentages have gone on to be accepted and passed around as factual for years. Amazingly, Ernie Rothkopf, professor emeritus of Columbia University, informed Thalheimer that these “bogus percentages have been widely discredited, yet they keep rearing their ugly head in one form or another every few years.”

Dale’s Cone
The other component that forms the melding is a diagram that has been dubbed Dale’s “Cone of Experience.” Thalheimer notes that the concept was first developed by Edgar Dale in 1946.

Dale’s cone was constructed as an intuitive model to describe “the concreteness of various audio-visual media.” However, though the diagram served as a likely key schematic to help with analysis, Dale did not conduct any research or use the research of others to construct the model.
Thalheimer adds, “Dale warned his readers not to take the model too literally.”

Readers will note that the original visual is devoid of numbers. The conclusion is simple, “Somewhere along the way someone unnaturally fused Dale’s Cone and Treichler’s dubious percentages.”

And unfortunately, despite the fact that the concept has no research basis, it has been passed around liberally for years on end.

Back to the Mea Culpa
Sometimes, in our push to get new content out, we select a visual that we later regret. Certainly that is the case here.

The former teacher in me demands what I always demanded of my students: when you make a mistake, admit it, learn from it, and most importantly, be sure to do better next time. In this case, the lesson is a little more painful.

Because this was not a rush job. I must admit I was not aware that the numbers had been as Professor Rothkopf insisted “widely discredited.”

Outdated? No doubt.

Never having any research basis? Mea culpa.

The Beauty of the Blogging World
Which brings us finally to the beauty of blogging - the chance to carefully examine and then correct what has been passed around as fact. Our thanks to Stephen for clarifying a long-standing error, and to Stephen for pointing us straight.

Our latest post stands as a record for some new found learning. And though our selected diagram appears here in this post, we have gone back to tidy up our deliberate practice article and removed the “Bastardization of Dale’s Cone” from it.

But in the process we have unfortunately established yet another skeleton. And the need for a bigger closet.

Of course, it should be duly noted that any chance at the Secretary of Education position in the Obama administration disappeared well before this latest gaffe.

Flickr photo courtesy of dkuropatwa.