Caveat Lector: Sample Selection in Historical Heights and the Interpretation of Early Industrializing Economies

Much of the research on height in historical populations relies on convenience samples. A crucial question with convenience samples is whether the sample accurately reflects the characteristics of the population; if not, then estimated parameters will be affected by sample selection bias. This paper applies a simple test for selection biased developed in Bodenhorn, Guinnane, and Mroz (2013) to several historical samples of prisoners, freed slaves, and college students. We reject the hypothesis of no selection bias in all cases. Using Roy's (1951) model of occupational choice, we interpret these findings as reflecting the economic forces that lead individuals to take the actions the led to inclusion in the sample. Our findings suggest that much of the evidence on the "industrialization puzzle" during the nineteenth century could reflect changing selection into the samples rather than changes in population heights.