(Chernoff) Faces of European Union.

There is a skill that all humans master: Facial Recognition. Humans developed this incredible capacity to detect faces, and most importantly, facial expressions, because it helped us to perceive social cues, making our groups stronges. Survival material! A side effect of this ability is that we got so good at it that we see faces everywhere, even when there's none.

In 1973 a mathematician named Herman Chernoff chose to explore this skill and created the Chernoff Faces. With them, we map data points to attributes of a face, creating a facial expression that can instantly communicate, in a very human-way, insights about the data. I decided to use this technique to create a Chernoff Face for each European Union country, based on a few social indicators.
Below is the result, and you can click in any country to learn more:

Each facial attribute is set from a data indicator from the specific country. The attributes that can be modified are mouth, nose, eyebrows, skin color and neck, based on the value of the data indicator. In the following sections, I'll explain each attribute and the data indicator used to set it.

Mouth

The Cantril Ladder index is a way to measure how happy people feel, based on a simple question: "On a scale from 0 to 10, how's your life going right now?" 0 is the worst life you can imagine, and 10 is the best. Here, with the average index from each country I decided to map these values to a mouth in a Chernoff Face. Seemed logical to relate "happiness" to the intensity of a smile.

I experimented with 3 different smiles: The very happy smile was given to all countries with Happiness scores in the top 25%. Those in the bottom 25% got a not so happy smile. Everyone in the middle got an unbothered smile.
The index for each country can be seen below.
Source.

Eyebrows

The Eurostat computes a metric called Perceived Corruption index, which indicates how corrupt governments are in the eyes of their citizens. People tend to become angry at governments when they are seen as corrupt, and the easiest way to express this anger in a Chernoff Face is through the eyebrows.

An angry look is given to countries with perceived corruption score in the top 25%, while a relaxed look is given to those with a score in the lowest 25%. Countries in the middle get a neutral look.
The index for each country can be seen below.
Source.

Nose

Take a deep breath. Was it refreshing? One way to measure this can be done by looking at the amount of suspended particles in the air, since they indicate pollution. These particules have less than 2.5 micrometers in diameter and their quantities are measured in µg/m3.

The nose in a Chernoff Face is the most obvious element to represent this value. Countries with a high amount of suspended particles got a bigger nose than countries with fresher air.
The index for each country can be seen below.
Source.

Skin

Do you like to get a tan? This can be easily achieved depending on the country you are. The amount of UV radiation someone is exposed to plays an important role in this goal, and such radiation can be measured J/m².

For the Chernoff Faces, each country gets a different "tan" based on the average amount of UV radiation they receive. More UV radiation gives a darker skin color, while less UV radiation gives a lighter skin color. The average UV exposure for each country can be seen below.
Source.

Neck

It is true that this classification may vary, but a common way to define obesity is using the Body Mass Index (BMI). A person with a BMI above 25 is generally considered obese. If the obesity rate in a given country's population is considered high, its Chernoff Face receives a proeminent neck, while countries with a low rate receives none.
The share of adults who are considered obese in each country can be seen below.
Source.