Dataset: Gapminder

## Team Alpha

* The range of GDP per capita increased significantly for all continents between 1952 and 2007. The median increased significantly for most continents, but not Africa

* Kuwait's GDP per capita in 1952 was a very significant outlier, so large that plots needed to exclude it to be legible. We wondered if this was linked in some way to their population being low, but it did not seem to be. Kuwait's GDP per capita dropped sharply around 1972, around the time the oil shock was starting.

1. ↑ Boxplots of GDP per capita by continent, 1952 and 2007
2. ↑ Kuwait's GDP per capita, compared to population

## Team Beta

**How has life expectancy changed over time per continent?**

* Mean `lifeExp` has increased monotonically for every continent…

* …but Africa still lags behind other continents. In the 90’s, Africa’s mean life expectancy plateaued (decreased?) until 2007.

**What relationship do `gdpPercap` and `lifeExp` have?**

* Epistemic status: moderate confidence. There is an exponential relationship between `lifeExp` and `gdpPercap`.
	+ Hypothesis: The longer people live, the more productive they are.
	+ But correlation != causation, and economies are complex systems.

**What relationship do `gdpPercap` and `pop` have?**

* Larger populations do not imply larger `gdpPercap.`
	+ …which should be obvious. `Percap` implies population-normalized data.

1. ↑ Beta 1 - Scatter + smooth for lifeExp vs. year (Github)
2. ↑ Beta 2 - gdpPerCap vs. lifeExp for year\_min, year\_max (Github)
3. ↑ Beta 3 - gdpPerCap vs. pop for year\_min, year\_max (Github)

## Team Delta

* Per capita GDP and life expectancy are correlated, with diminishing returns. This is known as the Preston curve.[2][3]
* Average life expectancy grew across every continent from 1952 to 2007.[4]
* There is minimal correlation between country population and per capita GDP or life expectancy.[5]

## Team Zeta

### **Despite a positive relationship between GDP per capita and life expectancy in 1952 and 2007, correlation does not imply causation**.

The trend previously discussed (higher GDP per capita associated with higher life expectancy) suggests that as GDP increases, life expectancy also increases. For the countries “‘worst-off’ to start in 1952, Lesotho and Afghanistan, there was not a direct correlation between GPD per capita and life expectancy as it changed over time. Meanwhile, for countries that started rich or with a higher life expectancy, Kuwait and Norway, the changes in life expectancy or GDP per capita were low and show a weak correlation though one is negative and does not align with the trend suggestion. Looking at a more holistic plot of GDP per capita and life expectancy over time, the trend is supported for the majority of datapoints (aside from the top six highest GDP per capita values). All of those datapoints are associated with Kuwait around their “golden period” where academics argued that only the wealthy and those connected to them were the beneficiaries, according to Kuwait’s Wikipedia page.

It’s also important to note that factors like war, famine, economic development, and accessibility and development of healthcare likely had an effect on life expectancy. For instance, both Afghanistan and Lesotho have experienced armed conflicts, famine, and widespread inaccessibility to healthcare throughout their histories.

### **While mean life expectancy and GDP per capita has increased globally, the distribution within each continent is widening.**

Widening distribution supports the idea that we are seeing increasing wealth inequality, which in turn is fueling populist movements globally.

### **The wealthiest nations with the lowest life expectancies are oil-rich, and tend to be authoritarian**

The wealthy countries (per capita GDP > 15,000) whose citizens have lower-than-expected longevity (life expectancy < 70) are Bahrain, Gabon, Kuwait, Libya, Oman, Saudi Arabia, and Trinidad and Tobago (only in the most recent year for which data is available, 2007). All of these nations are oil-rich, and most are authoritarian. All of them likely have high levels of wealth inequality (though this data is not included in our dataset).

1. ↑ Lesotho (poorest country in 1952) over time
2. ↑ Afghanistan (lowest GDP per capita country in 1952) over time
3. ↑ Kuwait (richest country in 1952) over time
4. ↑ Norway (highest GDP per capita country in 1952) over time
5. ↑ GDP per capita and life expectancy over time
6. ↑ GDP per capita by continent and year, 1952 and 2007
7. ↑ GDP per capita and life expectancy, wealthy but lower-life-expectancy nations highlighted in red