One of the most influential ideas in the study of political instability is that income shocks provoke conflict. “State prize” theories argue that higher revenues increase incentives to capture the state. “Opportunity cost” theories argue that higher prices decrease individual incen-tives...

Concern has intensified in recent years that many instrumental variables used in widely-cited growth regressions may be invalid, weak, or both. Attempts to remedy this general problem remain inadequate. We demonstrate that a range of published growth regressions may contain spurious results...