Polity’s regime score implies zero is the conceptual midpoint between democracy and autocracy.

Evidence

Given that the Polity measure of regime type is democracy minus autocracy, where both democracy and autocracy range from 0 to 10, there is much in the Polity procedure that would imply that 0 is the conceptual middle point. — Gary Goertz, Social Science Concepts and Measurement, 916

Categorization

• QUESTION: If 0 is the conceptual middle of a -10 to +10 scale, what happens to ‘neutral’ regimes that the raw subtraction treats as unclassified or anomalous?
• XREF: Connects to the broader measurement literature on ordinal vs. interval scales and the contested mapping of regime-type indicators.