Investigating the Relative Age Effect at Yale

An apple sitting on a pile of books

I just finished reading Malcolm Gladwell’s best-seller, Outliers. Naturally, I was curious about some of his claims and decided to do a little investigating of my own.

Gladwell starts the book by suggesting the existence of the following “iron law” of Canadian hockey: “in any elite group of hockey players — the very best of the best — 40 percent of the players will have been born between January and March, 30 percent between April and June, 20 percent between July and September, and 10 percent between October and December.”

Why would this be the case? It turns out that Canadian hockey leagues impose an eligibility cut-off date of January 1, meaning that a child born in January competes in the same league as a child born in December, almost an entire year later. These extra months of maturity, according to a study conducted by psychologist Roger Barnsley, give an unfair advantage to kids born earlier in the year — by virtue of being older, these kids tend to be larger, more coordinated, and more “talented” than their peers. Those that are deemed more talented go on to enjoy the rewards of better coaching, increased self-confidence, and more opportunities, creating a self-fulfilling prophecy that is driven entirely by an arbitrary cut-off.

This phenomenon is known as the relative age effect. And both Gladwell and Barnsley suggest that it occurs within academia and education as well. Like hockey leagues, schools have an eligibility cut-off date (usually, the end of summer) and often separate students based on relative merit (gifted student programs). To further this argument, Gladwell points to the research of economists Kelly Bedard and Elizabeth Dhuey, who have noted that “at four year colleges in the United States… students belonging to the relatively youngest group in their class are underrepresented by about 11.6 percent.”

With this knowledge in hand, I decided to poke around and see if I could find any interesting patterns at Yale, hoping to answer the following question: does the relative age effect impact your chances of making it to Yale?

Since I’m currently an undergrad at Yale, I have access to the walled-off Yale Facebook, a directory that contains basic biographical and contact information for all current undergraduate students. Here’s the scraped and compiled data, which includes the class of 2015 up to the class of 2019 (5565 students total, 5381 of which have their birthdays listed):

  • January: 475
  • February: 405
  • March: 468
  • April: 479
  • May: 461
  • June: 445
  • July: 446
  • August: 428
  • September: 443
  • October: 481
  • November: 425
  • December: 425

Birth months at Yale

It seems that the relative age effect doesn’t apply: Yale undergrads are born evenly throughout the year, with a range of 76, a mean of around 448, and a fairly low standard deviation of around 25. And the most unpopular birth month is February, which also happens to be the shortest month of the year. If we adjust for the 10 or so lost days of February between the classes of 2015 and 2019, the data would show even less variance than it does now.

However, it can’t hurt to point out that the graph has three local maximums, two of which might be relevant to the relative age effect: one around October (close to the start of school in the Northern hemisphere), one in March and April (close to the start of school in the Southern hemisphere) and one in January (which I don’t have a relavant explanation for).

It’s also worth noting that according to data compiled by Amitabh Chandra of Harvard University, the second half of September is the most common time of year for U.S.-born babies (approximately 81% of the Yale population hold U.S. citizenship or permanent resident status), providing an alternate explanation for that particular local maximum.

There are, unfortunately, some limitations to what we can do with this data. The Yale Facebook does not list birth years, which makes it impossible to filter out students who may have entered school a year early, or who may have skipped a grade or two. However, if we assume that these kids do exist in the pool, we might be able to say that the relative age effect did not play a role in their development — that is, for the truly precocious, relative age differences do not play a major role in their educational development. This isn’t a certain conclusion, however, since the other side of the coin in not having birth years is that we also are unable to filter out students who may have purposely “redshirted” before starting kindergarten or who may have taken a gap year in between high school and college, thus making them older than their peers by the time they enter college.

But empirically, at least, it appears that most early age biases at Yale have been erased or never existed in the first place. 1

Could it be that Yale admissions officers are familiar with the relative age effect and consciously adjust for this in their admissions process? This is possible, but probably unlikely.

Here’s another possibility: as mentioned earlier, 19% of Yale students are listed as international students. What if, out of this 19%, almost every student that attended school in the Southern hemisphere was born in the months of March and April, balancing out a presumably lower amount of students in the Northern hemisphere that were also born in those months? If true, this could have created the local maximum that we see in March and April. And while relying purely on geography is an imperfect filter for determining when school starts, it should at least give us a working estimate to play with.

When I went to test this hypothesis, I quickly discovered that this was not the case. Of the 83 students with addresses in the Southern hemisphere (Argentina, Australia, Botswana, Brazil, Chile, Indonesia, Kenya, Mauritius, New Zealand, Peru, Rwanda, Singapore, South Africa, Swaziland, Tanzania, Uganda, Zimbabwe), only 14 were born in March and April. The most common birth months were actually June and July.

The best explanation I’ve seen thus far comes from Maria Konnikova from The New Yorker. In her “Youngest Kid, Smartest Kid?” essay, Konnikova suggests that while older kindergarten students do benefit from their age, “by the time they get to eighth grade, any disparity has largely evened out — and, by college, younger students repeatedly outperform older ones in any given year.” Older students, she argues, become bored and complacent, while younger students embrace their underdog statuses and are forced to strive and push themselves harder, developing a work ethic that even Gladwell can appreciate.

Thanks to Jonathan Chang for reading a draft of this essay.

  1. Note: this experiment only tests for the relative age bias. I am positive that there are many other biases and barriers in this data set that can not be explained solely by age.


Single threading

Birthday candles

Hi, tomorrow is your sister’s birthday. You forgot mom’s.

Fuck.

My mother’s birthday was two days ago and I completely forgot. My sister’s birthday is tomorrow. Chances are, I might have forgotten her birthday too if my father didn’t text me a few hours ago.

How did this happen? With our fancy calendar apps and all their incessant push notifications, how could I possibly forget the birthdays of the most important people in my life? 1

Here’s my lame excuse: I’ve been so busy preparing for finals, writing papers, and working on my projects that I literally wasn’t thinking about anything else. The notebook that I carry around in my back pocket hasn’t had a new entry scribbled in it in over a week. I’ve been living from day to day, from class to class, from assignment to assignment. And I’ve basically lost track of the concept of time.

I didn’t even know the date.

This is me running on single threaded processing — moving from one task to another and being so absorbed in it that I forget everything else important to me. It’s just too easy to lose track of things when you’re working on hard problems or when you’re working through a lot of stress. Naturally, you start to lose mental cycles.

But that’s just so dangerous, even if it only happens rarely: being so insular and so single-threaded makes you lose perspective on the world. The people I love are so much more important to me than schoolwork, my health is so much more important to me than my pride, and solving big, meaningful problems is so much more important to me than solving the problem of picking where to go for lunch.

I hope I’m never so single-threaded, so single-minded, and so insular in my thoughts that I forget about the bigger picture and everything else that’s important to me. I need to force myself out of these self-imposed bubbles and take in all the little details around me.

Because frankly, I’m ashamed.

  1. Here’s the real kicker: I actually don’t have their birthdays in my calendar because I thought that it was impossible for me to ever forget them. It also just feels too impersonal and inappropriate for people so close to me.


Great Products are Aspirational

Mountains

What makes a product like Instagram so much more such successful than other, similar photography apps? What makes Apple computers so much more popular in the public eye? What makes Moleskine the de facto notebook for creative types?

These questions have been discussed ad nauseum and many convincing answers have already been suggested: these products had superior branding, were well designed, launched at the right times with the right set of features, and were technologically better (okay, maybe not the Moleskine). They executed relentlessly, found the right initial set of users, and then expanded quickly to capture the rest of the general public. All of these answers are satisfactory, but I think there’s another deeper explanation for why these products are so successful.

Good products must be useful. But to be great, they must also be aspirational. 1 Fundamentally, good products need to solve a problem; for the people that need them, they are utilities. If they’re better designed, better marketed, easier to use, and better timed than other products on the market, then the gears will be more greased for the product to succeed. But without achieving utility, even the best designed, best marketed products may not become massively successful.

To go from good to great, products have to connect with people who don’t necessarily need them. This means that they are aspirational products to those who don’t have the problem (yet!), but want to be a part of the group that does. Let’s look at some examples.

Instagram

  • Utility product: a mobile editor for photos (with a social network built on top)
  • Aspirational product: attracts everyday people with phones who want to have more interesting lives and cooler photos to share

Apple MacBook

  • Utility product: a laptop
  • Aspirational product: attracts creative types who want to use what their heroes use — for example, many musicians use Logic Pro, many directors and filmmakers use Final Cut Pro, and many programmers use Macs for its Unix-based OS

Moleskine

  • Utility product: a notebook to write in
  • Aspirational product: attracts people who want to write more, become more thoughtful, and seem more intelligent

Stripe

  • Utility product: a payment gateway that scales upwards
  • Aspirational product: attracts entrepreneurs who are currently building or are planning on building a SaaS startup or other online business

GoPro

  • Utility product: lightweight, mountable camera
  • Aspirational product: attracts people who want to live an extreme lifestyle

Product Hunt

  • Utility product: a place to launch your product and receive community feedback
  • Aspirational product: attracts a community of people who want to become creators and makers

So the product is 1) instantly useful to the people who need it and is 2) able to attract people who want to need it. Over time, many of these aspirational users may become utility users, allowing the product to continue to grow and expand its active user base. Aspirational Stripe users will build businesses that process so many transactions that they need the API to operate. By using their Moleskines more, non-writers will become writers (or at the very least, will consume more Moleskines as they attempt to write).

One could perhaps argue that superb branding creates this utilitarian-aspiration split, but I disagree. Building a product that has this sort of behavior will naturally lead to better branding, not the other way around, although I’m sure there are exceptions where better branding leads to aspirational desires.

  1. Note that by “aspirational,” I don’t necessarily mean that they are so expensive that they are out of the reach of the general public. I mean products that people yearn to use and desire to become part of the ingroup of.


Don't Sting Like a Bee

A honey bee landing on a flower

Muhammad Ali’s “…sting like a bee” strategy is metaphorically flawed. It certainly worked well for Ali, but the real world isn’t a boxing ring. Here, it rarely makes sense to sting like a bee.

Yes, bee stings are painful, but unless you’re allergic to them, a bee sting is nothing more than a brief annoyance. But it’s much worse for the bee. Let’s assume that we’re talking about a honey bee: these bees have barbed stingers that tear off and become lodged in the victim’s skin, causing the bee to die. 1

If stinging someone kills you, why would you ever do it? For a bee, stinging is a natural instinct: a bee stings when it feels threatened, releasing pheromones that will alert other bees to the impending danger. I think humans unconsciously behave much in the same way, but instead of dying when we “sting back,” we face unwanted consequences that could have been avoided with clearer thinking. We’re almost always better off not being too reactive when provoked. It’s better to take time to calm down, think things through, and then make the next decision instead of instinctively lashing out and striking back.

We often run into moments that test us mentally and physically, but the best thing to do is to persevere and to push through. Human nature is surprisingly flexible and adaptable: when presented with a barrier, we tend to find an ingenious way around it. Doing anything other than trying to make forward progress would be counterintuitive and counterproductive. Rather than instinctively blowing up, be it at ourselves, at someone else, or at a particular situation, we’re better when we transcend, when we accept what we’re given, and take things in stride.

In his State of the Union address last night, President Obama described this sentiment well:

My first duty as Commander-in-Chief is to defend the United States of America. In doing so, the question is not whether America leads in the world, but how. When we make rash decisions, reacting to the headlines instead of using our heads; when the first response to a challenge is to send in our military — then we risk getting drawn into unnecessary conflicts, and neglect the broader strategy we need for a safer, more prosperous world. That’s what our enemies want us to do.

I propose this same framework for managing a business: when provoked, don’t sting back. In a free market, one of the only guarantees is that there will be competition. If a new competitor enters your market or if an existing player unveils something that looks remarkably like something on your roadmap or something from your existing feature set, it doesn’t make sense to freak out and panic. It also doesn’t make sense to reactively change your game plan and become extremely defensive or aggressive. Don’t let someone else dictate your strategy!

Instead, it’s better to take a moment to sit back, evaluate the situation clearly and level-headedly, and then decide what to do. If a change in your product roadmap makes sense, then by all means make that change. But don’t change everything just because you feel threatened. Don’t sting like a bee. Be smarter, play by your own playbook, and keep going. That’s how you’ll eventually win, by being better, not by being the fastest to respond to conflict. 2

This doesn’t mean that you shouldn’t be spontaneous, it just means that you shouldn’t be rash. There’s a minor distinction between the two. Be spontaneous on a day-to-day basis by experimenting with and trying new ideas. Surprise and delight your customers when they aren’t expecting it. This is all fine. But when it comes to dealing with conflict and competition, don’t be too rash in your decision making.

This also doesn’t mean that you shouldn’t be confrontational, it just means that you should pick your fights wisely. There’s a time and place for “wartime” and “gathering the troops” in the “war room.” Most of the time, I’d argue that it’s not your battle to fight. 3

So sure, float like a butterfly, but don’t sting like a bee.

  1. The stinger only falls off when the victim’s skin is thick enough. So bees can actually sting other things (like non-mammals) without dying.

  2. Paul Graham writes, “Startups don’t win by attacking. They win by transcending. There are exceptions of course, but usually the way to win is to race ahead, not to stop and fight.”

  3. For the most part, I agree with this tweet from Joel Spolsky where he writes, “can we stop with the ‘war’ metaphor? It’s a job. programming computers. That’s not what wars are.”


What You Don't Do

"Two roads diverge in a yellow wood..."

"Two roads diverge in a yellow wood..."

What you do is important and can define who you are and what you stand for, but what you don’t do is perhaps even more important.

When the norm is to do something a certain way, choosing not to do it becomes glaringly obvious. And often times, not doing something that everyone else does can be one of the best things that you can do.

When everyone is raising huge rounds and making headlines, the companies that succeed quietly like WhatsApp earn our respect. When the popular Silicon Valley motif is “college kid drops out to start an internet company,” the ones who don’t command our attention. When other websites are focused on increasing time spent on their sites, the search engine that decides to decrease it becomes the most viewed website in the world.

Not doing something that everyone else does can also be one of the worst things that you can do.

Perhaps one of the best examples is how the majority of VCs tweet and blog actively. Not tweeting makes a VC seem inaccessible or untrustworthy. In a field based on trust, communication, and positive relationships, not tweeting can be detrimental to a VC’s ability to source great investments. And that’s without considering how many potential deals they might not be hearing about by not being active on Twitter.

It’s necessary then to think hard about what you do, what you don’t do, and why. Sometimes, you’re forced to do things not because you want to do them, but because you fear the consequences of not doing them. But there are things that you can consciously choose not to do that will become a key, positive part of who you are or what your company represents.

If you’re willing to take that risk and bear the consequences, you might find a huge opportunity to differentiate yourself from the pack.

Let’s consider taxis. Taxi drivers are generally pretty serious and professional about what they do: after all, it’s their job. Uber prides itself on a similar sense of seriousness and professionalism, but promises a much better user experience. Now consider Lyft, a company that actively chooses not to be serious with quirky, pink mustaches and drivers that are forced to fistbump you and engage in conversation. It’s ultimately subjective, but a lot of people love Lyft! And it’s all because they choose not to be serious: that’s their competitive advantage.

Yo is also a great example. It’s unclear how successful (or unsuccessful) it will ultimately become, but Yo has carved itself a niche with contextless push notifications, something so radically different (or useless, depending on who you ask) that it has everyone buzzing.

We’re always in search of outliers, but it’s not about being nonconformist for the sake of being nonconformist. It’s about thinking hard about the defaults and questioning them. Certain things you can’t choose not to do, like customer service or making something your customers actually want. But other things, like not being serious in a serious industry, can make all the difference.

At Aflume, we’re trying to shape the future of music by changing how artists and fans interact, but we aren’t trying to be the next website that everyone goes to for music. Everyone these days says, check out my videos on Youtube, stream my music on SoundCloud, buy my stuff on iTunes, support me on Bandcamp, fund my Kickstarter, follow me on Twitter and Facebook. And on each site, musicians are forced to build a new profile, rediscover their fans, and then find a way to integrate that into their artistic identity.

You’ve probably never heard of us, and that’s not because we work with a lot of independent artists. It’s because we’re not trying to build a platform where you find artists to support. We’re consumer facing, but we’re letting artists take full creative and artistic control of our product: we power artists’ websites and want to be the backend of the music industry. And for the first time online, artists can promote themselves instead of yet another platform that they have a profile on.

Hopefully, we’re not doing the right thing.

If you’re a musician and think what we’re doing sounds interesting, please reach out. We’d love to help you succeed.