Correlations and the reason why we do studies

Just a few correlations to keep in mind when you hear that some event is “statistically” correlated to another.

The correlation coefficient ranges from −1 to 1. A value of 1 implies that a linear equation describes the relationship between X and Y perfectly, with all data points lying on a line for which Y increases as X increases. A value of −1 implies that all data points lie on a line for which Y decreases as X increases. A value of 0 implies that there is no linear correlation between the variables

  • –1.0 A perfect negative relationship

  • –0.70. A strong negative relationship

  • –0.50. A moderate negative relationship

  • –0.30. A weak negative relationship

  • 0.0 No linear relationship

  • +0.30. A weak positive relationship

  • +0.50. A moderate positive relationship

  • +0.70. A strong positive relationship

  • +1.0 A perfect positive relationship

So let’s have a look at some very strong correlations:

Math doctorates vs Uranium (Correlation r=0.952257)


Japanese passenger cars vs Suicides (Correlation r=0.935701)


Drowning vs Power Generation (Correlation r=0.901179)


US Oil Imports vs Drivers Killed (Correlation r=0.954509)


See other Spurious Correlations at