I am trying to find out what the world distribution of life expectancy looks like.
I took the most recent WHO data from here and did a quick an dirty analysis in R. Here is the histogram as well as a normal distribution with the same mean and standard deviation as the actual data:
Does not look very normally distributed. In fact, the shapiro test confirms this impression:
Shapiro-Wilk normality test data: df$life_expectancy W = 0.94141, p-value = 4.338e-07
Commenters requested to weigh the life expectancy by population size.Well...the result is pretty ugly:
Apparently, the large populations of China and India produce disproportionally high bars. However, keep in mind that we are using averaged values which means that all the variation within countries is not represented by the histogram. We would actually have to have data on individual ages of death for a random sample of the world population to finally settle the question. :/
A few people thought it would be interesting to see what the distribution looked like if we plotted the number of people dying at each age, so I took data from the SSA (which admittedly isn't global data, but it's probably fairly reflective of the world overall) and plotted the number of deaths per 100,000 at each age.
This looks like it makes sense - the high death rate at birth, the plateau during the 20-40 range, then the rapid escalation past middle age, and eventual decline shortly after reaching the average life expectancy range.
However, while it looks a lot smoother than plotting the averages of individual countries, it's definitely not normally distributed.
If you extrapolate the above death rates using the global life expectancy of 71.0 instead of US life expectancy, the chart looks roughly the same, but is adjusted to reflect what the death rates of the planet most likely look like.