Does Income Inequality Lead to Terrorism? Evidence from the Post-9/11 Era

We study the influence of income inequality on terrorism. Using cross-national data for 79 countries for the 2002-2012 period, we show that endogeneity matters to the inequalityterrorism relationship, e.g., because of the distributional effects of terrorism. Once endogeneity is properly accounted for by means of an instrumental-variable approach, higher levels of income inequality result in more terrorist activity. This finding is robust to different definitions of the dependent variable, different estimation techniques and different instruments for income inequality. Our finding that inequality fuels terrorism is consistent with relative deprivation theory which argues that conflict results from frustration over the actual distribution of economic resources within a society

The Rise of Market-Capitalism and the Roots of Anti-American Terrorism

We examine the role of market-capitalism in anti-American terrorism, differentiating between level- and rate-of-change-effects associated with market-capitalist development and their respective relationship with anti-U.S. violence. Using panel data for 149 countries between 1970 and 2007, we find that higher levels of capitalist development - consistent with the capitalist-peace literature - coincide with less anti-American terrorism, while the marketization process has inflammatory effects on anti-American terrorism. These findings are further corroborated by system-level time-series evidence. We argue that a higher level of market-capitalism is associated with less anti-American terrorism by creating economic interdependencies and a convergence of pro-peace values and institutions, while the destabilizing effects of the marketization process may stem from the violent opposition of various anti-market interest groups to economic, politico-institutional and cultural change initiated by a transition towards a market economy. These interest groups deliberately target the U.S. as the main proponent of modern capitalism, globalization and modernity, where anti-American terrorism serves the purpose of consolidating their respective societal position. Our findings that the U.S. may ultimately become a less likely target of transnational terrorism through the establishment of market economies, but should not disregard the disruptive political, economic and cultural effects of the marketization process in noncapitalist societies

The reliability of replications: a study in computational reproductions

This study investigates researcher variability in computational reproduction, an activity for which it is least expected. Eighty-five independent teams attempted numerical replication of results from an original study of policy preferences and immigration. Reproduction teams were randomly grouped into a ‘transparent group’ receiving original study and code or ‘opaque group’ receiving only a method and results description and no code. The transparent group mostly verified original results (95.7% same sign and p-value cutoff), while the opaque group had less success (89.3%). Second-decimal place exact numerical reproductions were less common (76.9 and 48.1%). Qualitative investigation of the workflows revealed many causes of error, including mistakes and procedural variations. When curating mistakes, we still find that only the transparent group was reliably successful. Our findings imply a need for transparency, but also more. Institutional checks and less subjective difficulty for researchers ‘doing reproduction’ would help, implying a need for better training. We also urge increased awareness of complexity in the research process and in ‘push button’ replications

Political Capitalism: The Interaction between Income Inequality, Economic Freedom and Democracy

In this contribution we study the relationship between income inequality and economic freedom for a panel of 100 countries for the 1971-2010 period. From a panel causality study we find that income inequality has a negative causal effect on economic freedom, while causation does not run in the opposite direction. We argue that the negative effect of inequality on economic liberty is due to the elite’s political power stemming from its disproportionate control over a country’s economic resources. The elite uses this power to curtail economic freedom to defend its economic interests by discouraging innovation, competition and protecting its rents. Running a series of dynamic panel estimations, we show that the negative effect of income inequality on economic freedom is robust to different sets of controls and estimation techniques. Finally, we show that the dynamics of the inequality-freedom nexus are to some extent conditional upon a country’s political regime. When inequality is low, democracies enjoy comparatively higher levels of economic liberty, in line with the interests of a large middle-class. By contrast, economic freedom is lower in democracies (compared to strongly autocratic regimes with the same income distribution) when inequality is high. We argue that the latter finding corresponds to a system of political capitalism or captured democracy, where a powerful economic elite cooperates with politicians and bureaucrats for their mutual benefit

The reliability of replications: a study in computational reproductions

This study investigates researcher variability in computational reproduction, an activity for which it is least expected. Eighty-five independent teams attempted numerical replication of results from an original study of policy preferences and immigration. Reproduction teams were randomly grouped into a ‘transparent group’ receiving original study and code or ‘opaque group’ receiving only a method and results description and no code. The transparent group mostly verified original results (95.7% same sign and p-value cutoff), while the opaque group had less success (89.3%). Second-decimal place exact numerical reproductions were less common (76.9 and 48.1%). Qualitative investigation of the workflows revealed many causes of error, including mistakes and procedural variations. When curating mistakes, we still find that only the transparent group was reliably successful. Our findings imply a need for transparency, but also more. Institutional checks and less subjective difficulty for researchers ‘doing reproduction’ would help, implying a need for better training. We also urge increased awareness of complexity in the research process and in ‘push button’ replications

Observing many researchers using the same data and hypothesis reveals a hidden universe of uncertainty

This study explores how researchers’ analytical choices affect the reliability of scientific findings. Most discussions of reliability problems in science focus on systematic biases. We broaden the lens to emphasize the idiosyncrasy of conscious and unconscious decisions that researchers make during data analysis. We coordinated 161 researchers in 73 research teams and observed their research decisions as they used the same data to independently test the same prominent social science hypothesis: that greater immigration reduces support for social policies among the public. In this typical case of social science research, research teams reported both widely diverging numerical findings and substantive conclusions despite identical start conditions. Researchers’ expertise, prior beliefs, and expectations barely predict the wide variation in research outcomes. More than 95% of the total variance in numerical results remains unexplained even after qualitative coding of all identifiable decisions in each team’s workflow. This reveals a universe of uncertainty that remains hidden when considering a single study in isolation. The idiosyncratic nature of how researchers’ results and conclusions varied is a previously underappreciated explanation for why many scientific hypotheses remain contested. These results call for greater epistemic humility and clarity in reporting scientific findings