Does the public support embryo selection?

The most interesting articles that came to our attention this week

Examining the Fraternal Birth Order Effect and Sexual Orientation: Insights from an East European Population. Jakub Fořt and colleagues examine the fraternal birth order effect (whereby men with more older brothers are more likely to be gay). Analysing data from Croatia and Slovakia, they find that the fraternal birth order effect exists for lesbians too. Women with more older brothers are more likely to be lesbian.

Quantitative Political Science Research is Greatly Underpowered. Vincent Arel-Bundock and colleagues examine the statistical power of political science research. Analysing 16,000 hypothesis tests from 2,000 articles, they find that the median analysis has only about 10% power. They also find that only about 1 in 10 tests have at least 80% power to detect the consensus effects reported in the literature.

The economic origins of government. Robert Allen and colleagues compare two theories for state formation: the demand-side theory emphasising public good provision, and the supply-side theory emphasising extraction by elites. Using river shifts in ancient Iraq as a natural experiment, they find support for the demand-side theory. A shift away is associated with state formation, as it required farmers to cooperate in building canals for irrigation. 

The left-hand map shows the region before the river shifts; the right-hand map the region after the shifts. States expanded around settlements that needed irrigation.