Mayshar et al. (2022) apply an instrumental variables identification strategy to data from nearly 1,000 societies included in the Ethnographic Atlas to claim that cultivation of cereals (appropriable by elites), rather than increased land productivity following the adoption of agriculture, led to the development of the state. We show two things. (1) Evidence for the appropriability theory holds when moving from a tribe-chiefdom to a state and not more broadly. (2) Conclusions are driven by a handful of outliers with statistical significance at the 10% level lost with winsorization at 2.1% (or trimming at 1.2%) of locations by cereal advantage.

Online experiments have surged in popularity, but how credible are their published results? We examine the universe of hypotheses tested on Amazon Mechanical Turk and reported in leading journals between 2010 and 2021. We find evidence of widespread p-hacking, publication bias, and under-powered studies. The extent of the problems varies substantially across fields, with marketing particularly badly afflicted and little evidence of distortion in economics. We explore correlates of increased credibility and compare the online results to laboratory results from the same outlets, finding similar distortions in both, with bunching just above the significance threshold more pronounced on MTurk.