The thing that stood out was the countries with the low scores ("most peaceful"). They're countries well-known for low levels of religious belief. So I thought I'd try to get some data. I grabbed numbers on "no religion" from wikipedia, and looked at the relationship. There were a lot of countries really squashed up at the low end of non-religous percentage (left side), so I did a transform. Unfortunately a large proportion of "0% atheist" countries make a log-transform impossible - so I did a cube-root instead.
So here's my graph of Peace Index (Low = Peaceful) vs non-religious percentage (click for larger)
Interesting, eh?
Issues:
- "wealth" will be a confounding variable (poorer countries will on average be less peaceful and more religious)
- a few of the non-religious percentage figures are a bit rubbery, and my treatment of ranges (taking the upper end) less than ideal.
I'd like to improve this plot by getting other/better figures (e.g. I'd also like to try some of these), giving ranges where ranges were given and giving less weighting by the width of the range (make them smaller or paler or something, if the figures are really uncertain). I'd like to use other figures, and see what adjusting for wealth (say GNP per capita or somesuch) does. Just looking at some of the wealthy "western" countries, it looks like the effect remains, but would be weaker.
I'd also like to label the points!
But this is a good start, and I've spent all the time I can on it for now.