10.7910/DVN/BQ4SM6Grijalva, JessalaJessalaGrijalva0000-0002-2763-2126University of Notre DameHarvard Dataverse2026Social Sciencespower-sharingdemocracy measurementV-Demcomposite indexpsychometric validationAmerican political developmentGrijalva, JessalaUniversity of Notre Dame2026-03-122026-03-134409750748485140011560216762120439196291158851262054443type/x-r-syntaxapplication/pdfapplication/octet-streamapplication/octet-streamapplication/pdfapplication/octet-streamapplication/pdfapplication/octet-streamapplication/octet-streamapplication/octet-streamapplication/octet-streamtext/markdown1.0CC0 1.0Construction and validation materials for the Power-Sharing Index (PSI), a composite measure of de facto political power distribution across social groups. PSI uses five Varieties of Democracy (V-Dem) v15 indicators — Social Group Power (v2pepwrsoc), Gender Power (v2pepwrgen), Civil Liberties Equality (v2clsocgrp), Freedom from Torture (v2cltort), and Freedom from Killings (v2clkill) — aggregated via a hybrid method (geometric mean multiplied by normalized Polyarchy). The repository includes three Quarto documents: Phase 1 (measure construction and aggregation sensitivity analysis), Phase 2 (psychometric validation including internal consistency, dimensionality, and convergent/discriminant validity), and a publication-ready Appendix. Precomputed .rda results files allow reproduction of the Appendix without raw V-Dem data. All analyses conducted in R.Raw V-Dem v15 data (V-Dem-CY-Full+Others-v15.rds) is not included due to license restrictions. Download from https://v-dem.net/data/dataset-archive/ and place in data/raw/ to reproduce Phase 1 and Phase 2 from scratch. The Appendix renders from precomputed .rda files without the raw data.