Measuring change in source of leader support

This article introduces the CHISOLS (Change in Source of Leader Support) dataset, which identifies which leadership changes within countries bring to power a new leader whose primary support is drawn from different societal groups than those who supported her predecessor. The dataset covers all countries of the world with populations greater than 500,000 from 1919 to 2008. We discuss the underlying rationale of our data collection, provide some brief information about the coding rules and procedures, and share some descriptive statistics. We find that changes in sources of leader support are more common in democracies than non-democracies, but also that changes in sources of leader support often occur without irregular leader transitions or large institutional changes, even within non-democracies. CHISOLS can be productively combined with other datasets like POLITY, Archigos, and DPI that provide information about political institutions, modes of leader transition, and placement on a left–right policy continuum, but CHISOLS also provides something new that was not previously available. These data allow researchers to study the extent to which different types of policy change are associated with all leader transitions, with changes in political institutions, or with changes in the set of interests that leaders most closely represent; CHISOLS facilitates comparing the effect of leaders, interests, and institutions on policy change across a wide spatial temporal domain.