99% Invisible - 226- On Average

Episode Date: August 24, 2016

In many ways, the built world was not designed for you. It was designed for the average person. Standardized tests, building codes, insurance rates, clothing sizes, The Dow Jones – all these measurements are based around the concept of an … Continue reading →

This is 99% invisible. I'm Roman Mars. Your world has not been designed for you. In large part, it has been designed for the average person. Throughout your education, you've been given standardized tests and been graded by how well you perform compared to the average. Building codes, turns, rates, the Dow Jones, all these measurements are based around the concept of an average. And it's okay, we know you're not average. You're really special. Ah, thanks, Avery Trouffman. Well, I mean it, you're not average. No one is, not completely.

But the concept of average affects us all. Everything seems to be based around this reference point of average. And obviously, everything about society is built this way, but I'd never really thought of it until I dug into this new science that I'm a part of. This is Todd Rose. My name is Todd Rose. I am the director of the My & Brain Education program at the Harvard Graduate School of Education. He's also the author of the book The End of Average. But to get to that, first we have to start with the beginning of average, because it wasn't always a thing. The concept of average, because it wasn't always a thing.

The concept of average, as we know it, was pioneered by a Belgian mathematician and astronomer named Adolf Ketalai. So Ketalai is the person who actually coins the term the average man, and he is in like the 1830s, he is actually an astronomer in Belgium. Today the way that most people get a handle on any set of numbers is to calculate the average. But in Ketalais time, astronomers were some of the only people who did this. Basically, averages were a way to compensate for the imprecise tools that astronomers were working with in 1830. If you were trying to time the movement of Saturn, you would etch little scratches on your glass of your telescope,

and as soon as it crossed one, you'd start counting, and you'd stop counting after it crossed the other, and then you'd write it down. But you can imagine, like, even if you're off by half a second, it's gonna introduce a lot of error. And so, they realized if they wanted to make sense of taming the heavens, they needed more precision in their estimates.

And they realized that if you had, say, 10 measurements, and they were all slightly different, if you added them together and divided them by 10, you'd get a better approximation of the true measurement. If you just average together our measurements, you're way more likely to be closer to the truth, right? And you end up getting kind of a bell curve of measurement errors. Kevley was the first to take this tool of astronomers and apply it to people.

In the early 1840s, KELOLAY finds a data set of the chest measurements of 5,738 Scottish soldiers. KELOLAY added together each of the measurements and divided it by the total sum of the soldiers, and that result, 39 and 3 1,quarters inches, was one of the very first times a scientist had calculated the average size of a human feature. But he brings with it the idea of truth, that the average chest size is true, and that all the individuals are like error, that nature is striving for the average soldier. This means the average measurement is the true measurement,

the platonic ideal, the perfect Scottish soldier, as a chest that is 39 and 3 ¼ inches, according to Ketale. So he's the one that decides not only his average mathematically useful, it's morally the way to think about people. And so he basically finds averages anywhere he can possibly find them.

And he just has like a field day. He measures all kinds of other people and averages them. He creates something called the Ketalai Index for measuring ratios of average height and average weight. And actually, we still use it today. Just now it's called the Body Mass Index or BMI. Ketalai would say, if you talked about height, everyone, if they were optimally fed,

if they were under the same environmental conditions, would have been average. So his view was that what you're striving for is the continual improvement of the average of the group. And it wasn't all just physical. Kedaleg combs through various data sets for marriages, murders, and suicides, and calculates the averages for them. He figures out there's such a thing as a normal suicide rate, which is really, really bizarre at the time, almost scandalous. Nowadays, when we're so used to the stability of big, massive amounts of data, that it's hard to put yourself in their shoes, but like back then, they really thought that something like, say, suicide

was such a personal decision that there couldn't possibly be any pattern there. But suddenly there were patterns of body size, of intelligence, of birth, of death. People became statistics. Their behavior starts to become predictable. Suddenly, human life went by the numbers. So obviously, the first interpretation is, well, wait a minute, maybe there's no free will, right?

Maybe there's laws of society just like there's laws of physics. And so that kick started a whole bunch of people like Karl Marx, who loved Ketale. And Ketale becomes a huge star. In his time, Ketale was up there with the likes of Sir Isaac Newton. His science of averages was this remarkable cutting edgeway to assess the health, wellness, and progress of populations. He's really active in the 1820s, 1830s, 1840s, all the way into the 50s and 60s.

And the 1860s brings us to the US Civil War and to another super fan of Ketale's science of averages, Abraham Lincoln. When the Civil War is going in the North, Lincoln actually decides they're kind of getting their butt kicked, frankly. In large part because this war had gotten so huge and unwieldy, Lincoln doesn't really have a handle on the Northern Army. And he's like, look, we don't even know who our soldiers are.

We don't know how well fed they are. We don't know what kind of armor they need. We don't know how well fed they are. We don't know what kind of armor they need. We don't know anything about them. Lincoln decided that the Union Army needed more information about its soldiers in order to best distribute resources. So he ordered this enormous study to assess the Union Army physically, medically, and mentally. And then in explicit obedience to Ketalais' new science, averages were calculated and reported. They actually say, basically, we're following the father of this new field,

Ketalai. These freshly calculated averages informed the distributions of food rations and the design of weapons. For example, if you were going to create muskets, well, how far is the trigger? And you could actually calculate average reach for soldier. This also affected military uniforms, which used to be all custom-sum. But in the Civil War, so many people had to be outfitted that custom uniforms would be impossibly expensive. So the uniforms had to be mass-produced. But they couldn't be just all one big floppy size.

And so now they're realizing, oh, well, you know, if we break it into subtypes, like there's a large, and this is what we mean by it You know this big of a torso this brought a shoulders, you know small medium large That's gonna carry over into the way they think about the mass production of clothing. Yep. The size of small medium and large Which might be on your t-shirt tag those came out of this massive civil war study So you can thank Ketalai and Lincoln for that. This study in the civil war was the basis for the American military's long-standing philosophy of standardized average-based design. And that's going to become the fundamental design philosophy

from the civil war forward. So in 1926, when the army was designing its first ever fighter plane cockpit, engineers measured the physical dimensions of hundreds of male pilots and used this data to standardize cockpit dimensions. Of course, the possibility of female pilots was never considered. Of course. The size and shape of the seat, the distance to the pedals and the stick, the height of the windshield, even the shape of the flight helmets were all made to conform to the average 1920s male pilot, which changed the way the pilots were selected. You basically then select people that fit into that and then exclude people that don't.

And this cockpit design worked okay, up to World War II. What happened was though, is that in World War II, it became an Air Force War, right? That was the first time when the Air Force would be the determinant of who was gonna win the war, and we absolutely ran out of pilots. The government recruited hundreds of new pilots, an expanded military aviation.

There's been a bunch of money on fancy new planes. Although the cockpits were still designed for the average 1920s male pilot. And this new big bad military force was going to fly the fastest and the highest and be the best. But that's not what happened. They actually had a pretty massive decline in performance, including just a rash of deaths. Pilots were dying all the time. Even after the war ended, just in training, they could not control their planes. It became kind of part of the culture of the Air Force where, hey, it's just really dangerous to fly. No one knew what was going on.

Some people thought, well, these ain't propeller planes anymore, maybe these new pilots just can't deal with the new aviation technology. And then they were like, well, maybe you got to train them better, and they did their better training programs, and that didn't work. After blaming the pilots, the training programs, and the technology, it finally dons on them,

what if it's the cockpit? Maybe it doesn't fit us anymore. Their first instinct is to think, we've just gotten bigger as a people. So the old average from 1922 is just too small, right? We're just bigger and better and like, let's build a better average. So in 1950, researchers at Wright Air Force Base in Ohio

were tasked with finding this new average. And one of those researchers was a man named Gilbert S. Daniels. Daniels was a Harvard graduate who had written his thesis on the average sizes of his class mate's hands. He was 23 years old, small, skinny, nerdy, not a military man at all. And he travels all over the country to different air force bases, and his job is to take these tape measures and just measure like 147 different dimensions of body size. It's got to be the most tedious job ever.

And as Daniels is traveling around, from base to base, measuring thousands of airmen, he's realizing this incredible variability from person to person, even within this limited demographic of young men. As he was measuring hands and legs and wastes and foreheads, Daniels kept asking himself, how many pilots were actually average? So he reports back. So he goes to them and says, like, I think there's a problem with the average and he says, I just want to do this side study.

I want to know if we take the 10 dimensions of size that matter most for design. Like say, shoulder width, height, chest, circumference, sleeve length, et cetera. How many of these pilots are actually average on all 10 of those dimensions? Daniels crunched the numbers. And of the 4,063 pilots he measured,

not a single airman was close to average in all of the 10 dimensions. None. Not one. And it got even worse, like if you just used three dimensions of size, less than 5% of the pilots were average on those. So he quickly realizes, like, wait, now you know the problem, if you are designing something for an average pilot, it's literally designed to fit nobody. And then this new era of jet-powered aviation were pilots were making split-second decisions

that could be life or death. It really mattered that pilots could reach what they needed to reach in a cockpit. The military is spraying into action pretty much right away. For the military to be willing to basically drop generations of design philosophy, right? Because it doesn't take them more than a few years to just be like, you can't design on average anymore. Air Force engineers and contractors designed adjustable foot pedals and adjustable helmet straps and flight suits and adjustable seats. You just can't believe that we were building planes with no adjustable seats. That's how much faith we had in the average person. Once all the adjustable

elements and other design solutions were put into place, pilot performance soared. And of course, now we take this for granted. That equipment should fit a wide range of body sizes instead of standardized around one average. You wouldn't buy a car that didn't have adjustable seats, right? That's just crazy. And it seeps into there pretty quickly in terms of automobiles and then you see what's interesting is the whole idea of ergonomics that all comes off of this period of time. We're where to jump starts the science of ergonomics which is not just for office chairs.

Well it's really the study of work is what you could boil it down to but it really is a matter of matching people's capacities to the job. This is Professor Kyrissa Harris-Adamson, Director of the UCSF UC Berkeley Ergonomics Program. It's really important not to go with the average a lot of the time. If we want to incorporate, say, a handle into something, well we'll look up the Anthropometry data and make sure we identify the gripspan that we think is best. Or if we're designing a crank and we want it to be at a certain height, then we will go back to the Anthropometry data and figure out what makes the most sense to accommodate as much of the population as we can. Keeping in mind that in the US, most of the measurements we base our designs on still come from the US Army. That's primarily the source that we use in, say, ergonomic books or when we're designing for the workplace.

And what we found is that those numbers are actually all pretty representative today, except for weight and abdominal growth. Which is part of why the world is so hard for heavier people to navigate. The military might be considered a more fit population than the rest of us. So does this mean that like military measurements affect the way our cars are designed? Absolutely. The measurements of our military personnel over the years affect just about everything. Military measurements are the most public and accessible.

And they work okay. They're not perfect, sure, but they're getting more inclusive. They've done a really good job in a calm day more of the population, given that women are now a very vibrant part of our military force. When the military opted to design for a greater range of people, they designed for a greater range of opportunity. Take for example, Kim Campbell. She was a fighter pilot and she flew a A10 Warhog and if it's worth googling,

it is like the baddest looking plane you're ever gonna see. That's Todd Rose again, by the way, helping us tell the story of Captain Campbell. In 2003, Campbell was sent on a mission to assist some Marines who were trying to take a bridge in Iraq, they were under heavy fire, but on her way back her plane gets shot and she loses all control. She has the option to eject right there and save her life, but then the plane spirals into Baghdad and kills a bunch of innocent people. So she says like I'm not going to do that. She stabilizes,

which I don't even know how you do. And she flies back and then she says, look, I think I can land this plane. And she lands the massive, damaged, uncontrollable plane. It's an incredible heroic feat, really unprecedented. So of course, Kim Campbell gets awards and distinctions. And she is someone who could have never been one of the best pilots in the world, had the military not changed their design philosophy. She's the beneficiary of a cockpit that's flexibly designed because she's like five, four, and rail thin and doesn't look anything remotely close to an average sized pilot.

When Kim gets into a cockpit, she has to put the seat all the way up and pull the pedals all the way out, but it fits. This idea of equal fit as the foundation for how we think about real opportunity in society, I think has serious consequences for the future of design. In this concept that fit makes opportunity, it's an important one for Todd, because he believes that we can design environments and equipment and even entire systems to accommodate more and more people. When we think about how we design environments,

in a lot of fields, we've made some progress around accommodating wider ranges of people, but actually in things like education, we still actually design for this mythical average person under the assumption that if you design something that fit an average person, it would actually fit most people. By re-examining the concept of the average and acknowledging its limitations, we can maybe start to consider other ways of assessing and categorizing test scores or clothing sizes

or wellness or happiness or worth. We can pave the way for more people who are outside of the average, because really, no one is average. 99% of visible was produced this week by Avery Trouffleman, which refutes of Katie Mangle, Emmett Fitzgerald, Kurt Colstead, Sam Greenspan, and me Roman Mars. If you want to know more, maybe you want to know how average came to mean subpar, instead of ideal, check out Todd Rose's book, it's called The End of Average, how we succeed in a world that values sameness. We had music, Marpal, okay, Akumi this week and lots of Lelotone, love Lelotone,

full track list and links to purchase at 99pi.org. We are a project of 91.7 KALW, San Francisco, and produced on Radio Row, the corridor of Broadway, where all the radio is made. In beautiful, downtown, Oakland, California. We're taking off next week to take some deep breaths and recover from the extra work we've had to do with different people being away on vacation, so look for us in two weeks. I hope you're taking some time off too. If you find yourself in need of a story, I bet you can find one you didn't hear the first time on leadylinepi.org.

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