The colonial origins of comparative development

"In a seminal contribution, Acemoglu, Johnson, and Robinson (2001) argue property-rights institutions powerfully affect national income, using estimated mortality rates of early European settlers to instrument capital expropriation risk. However 36 of the 64 countries in their sample are assigned mortality rates from other countries, typically based on mistaken or conflicting evidence. Also, incomparable mortality rates from populations of laborers, bishops, and soldiers - often on campaign - are combined in a manner favoring their hypothesis. When these data issues are controlled for, the relationship between mortality and expropriation risk lacks robustness, and instrumental-variable estimates become unreliable, often with infinite confidence intervals"--National Bureau of Economic Research web site.