At this point in time, the correlation between the Heritage Foundation's index of economic freedom and economic growth is unambiguously negative. I suspect this is because being a poor country is associated with low economic freedom but high catch-up growth.
To test this hypothesis, I did a linear regression of overall score, each of the ten subscores and 2013 real GDP growth against the log of 2013 GDP per capita (at parity). I then took the correlation between the residual of 2013 real GDP growth and the residual for each of the scores.
The analysis I'd do would be simpler. Compute the correlation of log GDP per capita with the freedom index (or its subscales); if I'm right it should be substantially positive. Then correlate log GDP per capita with GDP growth; the result should be substantially negative. Taking correlations of residuals addresses the different question of whether unusually high growth for a country's income level correlates with unusually high freedom indices for a country's income level.
I did the simpler analysis first and all the correlations between log GDP per capita and all the economic freedom index subscores were pretty negative (as was the correlation between log GDP per capita and GDP growth). Log GDP per capita was positively correlated with economic freedom subscores.
Edit: clarity
What is something you used to believe, preferably something concrete with direct or implied predictions, that you now know was dead wrong. Was your belief rational given what you knew and could know back then, or was it irrational, and why?
Edit: I feel like some of these are getting a bit glib and political. Please try to explain what false assumptions or biases were underlying your beliefs - be introspective - this is LW after all.