Social Data Commons: Segregation Index (HOI) (v2.0.1)

Overview Residential segregation indicator computed as the Entropy Index (Theil's H) from ACS table B03002 (Hispanic or Latino Origin by Race) race/ethnicity data, measuring how sub-area racial/ethnic composition differs from the overall state composition. The index uses eight race/ethnicity categories: Hispanic/Latino, White, Black, American Indian, Asian, Native Hawaiian/Pacific Islander, Some Other Race, and Two or More Races. Builds on methodology used in the Virginia Department of Health's Health Opportunity Index (HOI). This dataset is produced by the Social Data Commons at the University of Virginia as part of the Segregation data pipeline. Provenance The segregation indicator uses the Entropy Index (Theil's H), a method for measuring multigroup residential segregation that quantifies how sub-area racial/ethnic composition differs from the overall composition (Theil, 1972; Reardon & Firebaugh, 2002). This pipeline builds on methodology developed by the Virginia Department of Health, Office of Minority Health and Health Equity (VDH-OMHHE) for the Health Opportunity Index (HOI), which includes a segregation indicator as one of its 13 community health profiles. Coverage Temporal coverage: 2015–2024 (ACS 5-year estimates) Geographic levels: Block Group, County, Tract Coverage areas: National Capital Region (DC metro), Virginia (statewide) Methodology The Segregation Index measures how much a community's racial and ethnic composition differs from the state as a whole, using the Entropy Index (Theil's H) across eight racial/ethnic categories. Communities with high segregation values tend to have more concentrated poverty, unequal access to services, and wider disparities in educational and economic outcomes. As a component of the VDH Health Opportunity Index Social Impact profile, this measure helps identify areas where residential sorting by race may reinforce structural inequities. Source Tables ACS 5-Year Estimates, Table B03002 (Hispanic or Latino Origin by Race) Variables B03002_001: Total Pop B03002_012: Hisp Latin B03002_003: White B03002_004: Black B03002_005: American Indian B03002_006: Asian B03002_007: Nhopi B03002_008: Sor B03002_009: Two Measures (1) Note on naming conventions: Measures containing _geo20 are reported on 2020 Census tract boundaries. Pre-2020 estimates are standardized from 2010 to 2020 census tract boundaries using an area-based crosswalk: intensive measures (rates, percentages, medians, per-household quantities, densities, and composite indices) are assigned the value of the area-dominant 2010 tract rather than area-averaged, so the measure's scale is preserved. segregation_indicator_geo20: Segregation Indicator (mean, unit: index score) Entropy Index (Theil's H) measuring how sub-area racial/ethnic composition differs from the overall state composition. Data Sources U.S. Census Bureau (accessed 2025) File Format Data files are provided as CSVs (.csv) with the following columns: geoid, year, measure, value, moe (margin of error, where available), region_type, data_method (observed, modeled, scaled, interpolated, or extrapolated). Per-measure metadata (descriptions, units, and sources) is documented in the dataset's measure_info.json in the Social Data Commons repository.