What You Miss When You Focus on the Average | Sharon Zicherman | TED

In March 2022, I was diagnosed with colorectal cancer.

Within days, I had learned

that the cancer had already penetrated the walls of my colon

and spread to multiple lymph nodes.

My doctor explained that this was categorized as Stage 3C.

I immediately sought to educate myself about the disease and its treatment.

I found a study that said the chances of me surviving more than five years

was about 50 percent.

I was 39 years old at the time.

I wasn't a health nut, but I was active.

I didn't always make the best food choices,

but I didn't consider myself unhealthy either.

How could it be that the odds of me surviving to my 44th birthday

were no better than a coin flip?

Initially, I was paralyzed by that number.

But then I realized that I wasn’t just a number,

and neither were the other people in that statistic.

The average survival rate included people much older than me.

People with different lifestyles and histories,

some with genetic preconditions

and others who may have been heavy smokers for decades.

This realization prompted a fundamental shift in my thinking.

So I started to deeply question how we use averages,

especially in moments that shape our lives.

I'm a management consultant,

and my job is often to deconstruct data into its finer granularities.

What is commonly called de-averaging.

I look beyond surface-level averages

to help my clients understand their customers' needs

and take the right decisions on things such as pricing or service.

As I navigated my own diagnosis,

three key questions emerged about averages.

One: Is the average the right metric?

Two: Am I focusing on the right average?

And three: What am I missing by focusing on the average?

First: Is the average the right metric?

When designing a car or cooking a meal, it's common to aim for broad appeal.

People often target the average person.

But there are instances where the average is the wrong metric altogether,

especially when managing risk.

Take the Burj Khalifa, for example.

While Dubai is not situated on a tectonic fault line,

it does experience earthquakes.

On average, there are 52 earthquakes in the UAE per year,

most of a magnitude four on the Richter scale.

Yet the tallest building in the world, the Burj Khalifa,

was designed to withstand a 7.0 magnitude earthquake

because the developers decided to look beyond the averages

in their planning.

Can you imagine the implications

if they had planned for the average intensity of earthquakes in the region?

Designing a safe structure requires planning for more

than just the average risk.

And this applies to our everyday decisions, too.

One family movie night,

I chose a scary movie that was age-appropriate

based on the average age in my household, 23.

Needless to say, my six-year-old got very little sleep that night.

The average was simply not the right metric.

Second question:

If the average is the right metric,

ask yourself if you're considering the right average.

For instance, I've never witnessed someone using

an automated external defibrillator, or an AED.

I know where they are in my office, and I’ve noticed them in restaurants,

but I've never seen one in action.

Have you?

The reason is that on average,

there are about 200 cardiac arrests in public spaces in the US daily.

And in only 10 percent of these cases does a bystander use an AED.

The average usage of an AED must be very low,

but the value of having an AED accessible

isn't based on the average likelihood of witnessing a cardiac arrest

or using an AED.

It's about the impact when one is used.

Every minute after a cardiac arrest,

your chance of survival decreases by seven to 10 percent.

If you receive an AED shock within the first minute,

your chance of survival can jump to nine in ten.

In this case, focusing on the right metric,

the potential impact of having an AED,

makes all the difference in rationalizing why we invest so much.

This was the case with my cancer diagnosis as well.

The survival statistic that I encountered

was based on broad data covering many ages and geographies.

What I didn't know initially

was that over 80 percent of colorectal cancers

occur in people over the age of 49,

10 years older than I was.

Plus, this data was outdated

and didn't consider my specific treatment plan,

which had only been developed in recent years.

If you've decided to rely on an average to make decisions,

make sure it's the right one.

Ask yourself,

what does this average include that may not be relevant in my situation?

And is there a more relevant average that applies based on my context?

Anyone who's driven in LA knows the difference between planning

for the average commute versus the rush-hour commute.

Finally, if the average is the right metric

to look at for your objective

and you're looking at the most relevant average,

you still need to ask yourself the third question:

What am I leaving out by focusing on the average?

My first job was at a real estate investment firm

before the subprime mortgage crisis.

We all know how that worked out for many of the players,

but firms that survived relatively unscathed

did so because they didn't just focus

on the average default rates when analyzing investments.

They examined the worst case scenarios,

the outliers that had the potential to tank investments' entire value.

Learning from the averages often means ignoring the outliers,

but there's a lot that we can learn.

In his book "Cured,"

Dr. Jeffrey Rediger explores spontaneous remissions

in terminally ill patients.

These so-called "miracle cases" often defy scientific understanding

and are typically dismissed as statistical flukes.

Surely some of these are.

But what if we studied these outliers more closely?

They could hold valuable insights even if they don't fit the average mold.

What may not be statistically significant for the average patient

could make all the difference for an individual patient.

It's critical that when we decide to use the average

and are looking at the right one, we also consider outliers.

Otherwise, we could find ourselves getting an average medical treatment

instead of one tailored to our specific needs.

I was fortunate enough not to be a terminal case

like those that Dr. Rediger studied.

But after reconsidering the average,

I realized that 50/50 odds wouldn't be relevant in my case.

I set a different metric for my own survivorship,

and I'm targeting 100 percent.

Thank you.