The unsettled effect of physical height on political preferences

We revisit Arunachalam and Watson's contention that a person's physical height may be used as instrument for income because it affects economic well-being solely by causing more conservative political preferences among people who are taller. To evaluate whether other early-life and genetic factors might serve as mechanisms connecting height and political preferences, we analyze a unique data source that includes political, economic, and demographic data on same-gender siblings. Models that include fixed effects for siblings provide a strong test of the Arunachalam and Watson thesis. We find that height is not a consistent predictor of political preferences once shared sibling characteristics are controlled in this way, raising doubt about whether height can in fact be used as an instrument for income.