Exit, Voice and Political Change: Evidence from Swedish Mass Migration to the United States; A Comment

TL;DR

This paper critically examines the causal link between mass emigration and political change, highlighting methodological flaws in previous instrumental variable analyses and showing that correcting these issues negates the proposed relationship.

Contribution

It identifies key problems in prior instrumental variable approaches and demonstrates that, when addressed, there is no evidence of a causal effect of emigration on political outcomes.

Findings

Instrument violates exclusion restriction due to unaccounted confounders.

Measurement error in emigration data affects analysis.

Corrected analysis shows no causal relationship between emigration and political change.

Abstract

In this comment, I revisit the question raised in Karadja and Prawitz (2019) concerning a causal relationship between mass emigration and long-run political outcomes. I discuss a number of potential problems with their instrumental variable analysis. First, there are at least three reasons why their instrument violates the exclusion restriction: (i) failing to control for internal migration, (ii) insufficient control for confounders correlated with their instrument, and (iii) emigration measured with a nonclassical measurement error. Second, I also discuss two problems with the statistical inference, both of which indicate that the instrument does not fulfill the relevance condition, i.e., the instrument is not sufficiently correlated with the endogenous variable emigration. Correcting for any of these problems reveals that there is no relationship between emigration and political outcomes.