Rasch model and anchoring vignettes for metrological characterisation of a democracy measuring system: preliminary studies

Efforts to enhance democracy measurement systems lack integration of fundamental metrological principles. The implementation of the Rasch model, which arises as a potential solution for providing metrological traceability to psychosocial measures, remains unexplored in democracy measurement literature. This study applies the Rasch model to an anchoring vignettes database from the Varieties of Democracy (V-Dem) project, analysing coders' responses to the indicators that constitute the V-Dem expert survey on Deliberation. The proposed method for metrological characterisation evaluates the system's performance, considering the expert coders playing the crucial role as the sensing element and the questionnaire-defined indicators assembling the measuring system's structure. Sources of measurement uncertainty are specified within the measurement model. This preliminary study reveals items associated with critical elements, including differential item functioning based on coders' continent of origin and secondary dimensions affecting the sensor. Addressing these elements can enhance the reliability of democracy assessment and advance political science research.