Americans vs. non-Americans:

Americans (n=61): L/R economic is -3 (SD 4.08) and Lib./Auth. is -4.53 (SD 1.99)

Non-Americans (n=29): L/R economic is -3.95 (SD 4.38) and Lib./Auth. is -5.4 (SD 1.77)

According to the t-tests, assuming a 95% level of confidence, the differences between means on the economic scores is not significant. It can't be said with confidence that the differences are due to anything other than chance. However, on the social scale, the differences between means are significant. So it appears that there's something about US nationality among IIDB'ers that causes us to differ somewhat on social values.

Left vs. Right Quadrant:

Left quadrant (n=79): Lib/Auth. is -5.1 (SD 1.92)

Right quadrant (n=21): Lib/Auth. is -3.92 (SD 1.57)

According to the t-test, the difference between means here is significant, assuming a 95% level of confidence. So among IIDB'ers, there's something about being economically left that associates them with being a little more socially liberal than the those from the right quadrant.

lpetrich makes a similar observation:

lpetrich wrote: That may be why I've found a significant correlation between economic left/right and social libertarianism/authoritarianism; bottom left to top right in the Political Compass graph.

Capitalist libertarians are rather odd in being more socially libertarian than what one might expect from the overall population; they are in the bottom right. Furthermore, they expect the natural line of variation to be from the icky statists of the top left to the good freedom-lovers of the bottom right. But that expectation is falsified by the overall behavior of all the test scores I've collected so far.