Measuring Citizen and Government Ideology in the US States: A Re-appraisal

Berry et al.'s (1998) measures of U.S. state citizen and government ideology rely on unadjusted interest-group ratings for a state's members of Congress to infer information about (1) the ideological orientation of the electorates that selected them or (2) state legislators and the governor from the same state. Potential weaknesses in unadjusted interest-group ratings prompt the question: Are the Berry et al. measures flawed, and if so, can they be fixed by substituting alternative measures of a member's ideology? We conclude that a version of the Berry et al. state government ideology indicator relying on NOMINATE common space scores is marginally superior to the extant version. In contrast, we reaffirm the validity of the original state citizen ideology indicator and find that versions based on NOMINATE common space scores and adjusted ADA and COPE scores introduced by Groseclose, Levitt, and Snyder (1999) are weaker.