What is the “average” student? (Part I)

99piI’m not sure how many of you listen to podcasts, but for me, it’s almost all that I listen to – in the car, on a run, working on the yard – if my earbuds are in, I’m probably listening to a podcast.  I used to love to listen to talk radio, but the commercials drove me crazy, not to mention that I had to put up with topics that didn’t interest me to get to the interesting stuff.  One of the great things about podcasts – you only have to download the ones you find interesting.  If you don’t like a topic, don’t download it.  There are a couple of podcasts that I listen to no matter what the topic is.  The other day I was listening to one of my favorite podcasts, 99% Invisible.  It’s a show all about design, but looks at it from all kinds of perspectives – sometimes architecture and infrastructure, sometimes history, sometimes visuals, even a series on vexillology, which is the study of flags (I know, I’m a geek!).

the-end-of-averageOne of the most recent episodes was titled “On Average.”  Much of this episode is based on the work of Todd Rose, author of The End of Average.  One of the things that I found most interesting was that Rose, who is a professor at Harvard, is also a high school dropout.  His research on the science of individuality is based on his learning that nobody truly fits the average – more on that later.

So where does the idea of average come from?  While there are some mathematical references that go back to ancient history, the first scientific documentation of the idea of averages comes from astronomers in the 16th century.  In tracking the orbits of planets, astronomers would scratch the lens of a telescope in 2 spots and keep track of the amount of time it took the planet to move.  Astronomers realized that individual measurements could be highly inaccurate based on who was taking them, and other factors.  However, by taking many measurements and finding the average, the data seemed more accurate among multiple astronomers.

Fast forward to the 1800s, and a Belgian mathematician named Adolphe Quételet.  He decided to take a tool primarily used by astronomers and apply it to people.  He started with a data set of thousands of Scottish soldiers, and found that the average chest size of the soldiers was 39 and three-quarters inches.  He considered this to be the “true” size of a soldier.  Quételet extrapolated this data to say that if all lived in optimal conditions, they would be average.  Over time Quételet’s ideas expanded to find the normal rates based on all kinds of data sets – marriages, murders, suicides, etc.  Quételet went so far as to say that the individual person was synonymous with error, while the average person represented the true human being.

One of Quételet’s fans was none other than Abraham Lincoln.  During the Civil War, Lincoln had the army take data on soldiers to assess them both physically and mentally.  The data sets were then used to decide on appropriate food rations, design of weapons, even the size of uniforms.  Prior to the Civil War, every soldier received a uniform that was custom made.  With the number of uniforms necessary, this was no longer feasible, so the soldiers were broken into average sizes (small, medium, and large) so that uniforms could be mass produced.  Today we buy clothes based on sizes that relate back to these measurements from the armed forces.

Average based design became the way for the military, and from the time of the Civil War until World War II, everything built for the military was designed based on the average size of the soldiers.  Whether we’re talking about uniforms, bedding, food rations, weapons, vehicles, and as they came into use, airplanes, all were built to specifications that matched the average size data.

During World War II, the Air Force noticed a huge decline in the performance of pilots.  As the first air based war, this was a problem.  Initially blame was placed on the pilots, then on the trainers.  In time, the Air Force realized the issue was the size of the cockpit.  The cockpit didn’t fit the pilots.  As a fighter pilot, when split second decisions can make a difference between survival, the Air Force saw that they needed to find a new average.

Researchers at Wright Air Force base in Ohio were tasked with finding new averages.  Members of the team traveled from base to base taking measurements of pilots on 140 dimensions (some were the obvious – height and weight – while others were much more unique – length of the thumb or the distance from a pilot’s eye to his ear).  One of the members of the team was Gilbert Daniels, a recent graduate from Harvard in the field of anthropology.  As he was taking the measurements, Daniels started to wonder how many of the pilots truly were average.

Daniels took the data from a set of just over 4,000 pilots.  He found averages on the 10 measurements that would be considered the most important in terms of the design of an airplane cockpit and set up norms based on a 30 percent range (the average height in the study was 5-9, so the range was 5-7 to 5-11).  He then he went back to the individual data.  The assumption going in was that most pilots would fit the definition of the average pilot.  When he compared the individual measurements of all the pilots in the data set, he was stunned to find that not one of the pilots fell within the average range on all 10 dimensions.  When they narrowed the study to only 3 dimensions, less than 4% of the pilots met all 3.

The research showed that there was no such thing as the average pilot.  Instead the data looked a little like this:

airforce-dimensions
Rose describes the variation that shows in these measurements as Jaggedness – which represents that fact that everyone has variations from the norm or average.

In response, the Air Force made significant changes to their design process.  No longer would they buy airplanes that had cockpits that were designed to the average.  The Air Force banned the average for design of airplanes!  Instead they needed planes to be designed to the edges.  Prior to World War II, the pedals, seats, helmets, controls, and anything else in a plane was static, it could not be adjusted.  Following the results of this study, the Air Force demanded adjustable seats, foot pedals, helmet straps, and more.

When the change was made, guess what happened?  Pilots got better!  No longer did they have to adapt to the size of the plane.  Now all planes can be adapted to the size of the pilot.  Think about it, how many of you would purchase a car that did not have adjustable seats, mirrors, or steering wheel?  These adjustable features came about thanks to the Air Force’s research on averages.

I know that this post hasn’t gotten into the education implications yet – I promise that’s where I’m going next week.  To help next week’s post make more sense, we needed some background information about averages.  Next week we’ll get into how the research on the science of the individual translates into the classroom, and what we can do to design education to the edges, not just to the average.

What thoughts do you have?  Do you already see a connection between this backstory and your students today?  Share your thoughts in the comments below.

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