P-Values on the Free-Slave State Border: A Critique of Bleakley and Rhode

Francis, Joseph (2025): P-Values on the Free-Slave State Border: A Critique of Bleakley and Rhode.

Abstract

Hoyt Bleakley and Paul Rhode use a “regression discontinuity design” (RDD) to find a persistent negative effect of slavery’s legality on rural population density throughout the period from 1790 to 1860. Yet their reported results cannot be replicated. Instead, the replication shows slavery’s negative effects only become statistically significant from 1840 onwards. Furthermore, the addition of an interaction term for slavery’s legality multiplied by longitude suggests that slavery may have facilitated the westward expansion of the Southern frontier in the antebellum period. This does not support the claim that slavery impeded the growth of American capitalism.

• Item Type: MPRA Paper
• Language: English
• Keywords: Slavery, American capitalism, economic history, replication, regression dis-continuity design
• Subjects: C - Mathematical and Quantitative Methods > C2 - Single Equation Models ; Single Variables > C21 - Cross-Sectional Models ; Spatial Models ; Treatment Effect Models ; Quantile Regressions; J - Labor and Demographic Economics > J4 - Particular Labor Markets > J47 - Coercive Labor Markets; N - Economic History > N1 - Macroeconomics and Monetary Economics ; Industrial Structure ; Growth ; Fluctuations > N11 - U.S. ; Canada: Pre-1913; N - Economic History > N2 - Financial Markets and Institutions > N21 - U.S. ; Canada: Pre-1913; N - Economic History > N5 - Agriculture, Natural Resources, Environment, and Extractive Industries > N51 - U.S. ; Canada: Pre-1913; O - Economic Development, Innovation, Technological Change, and Growth > O4 - Economic Growth and Aggregate Productivity > O43 - Institutions and Growth

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