Contextual Data
GeoMarker attaches contextual data to your point data by determining the census geographic unit in which each point lies and attaching characteristics of that unit to the point record. The initial release of GeoMarker attaches data from the 2016 American Community Survey 5-year data at the census tract level. Future releases of GeoMarker will include additional datasets, geographic levels, and contextual variables. We want to know what additional data are important to you! Please send us your suggestions by emailing geomarker@umn.edu.
Point in Polygon: Determining Points’ Contexts
GeoMarker uses a basic point-in-polygon spatial operation to determine the geographic unit in which each latitude-longitude point is located. GeoMarker uses the 2016 Census Tract, 2016 Tiger/Line + basis shapefile, as provided by NHGIS as the definition of the polygons for the point-in-polygon operation. Contextual variables are derived from the 2016 ACS 5-year (2012-2016) dataset in NHGIS, using the following definitions.
Contextual Variables
| Proportion unemployed | |
|---|---|
| Source Table | B23025. Employment Status for the Population 16 Years and Over |
| Universe | Population 16 years and over |
| Numerator | [AF67005] In labor force: Civilian labor force: Unemployed |
| Denominator | [AF67003] In labor force: Civilian labor force |
| Proportion population in poverty | |
| Source Table | C17002. Ratio of Income to Poverty Level in the Past 12 Months |
| Universe | Population for whom poverty status is determined |
| Numerator | [AF43002] Under .50 +[AF43003] .50 to .99 |
| Denominator | [AF43001] Total |
| Median household income | |
| Source Table | B19013. Median Household Income in the Past 12 Months (in 2016 Inflation-Adjusted Dollars) |
| Universe | Households |
| Numerator | [AF49001] Median household income in the past 12 months (in 2016 inflation-adjusted dollars) |
| Denominator | n/a |
| Income inequality | |
| Source Table | B19083. Gini Index of Income Inequality |
| Universe | Households |
| Numerator | [AGL1001] Gini Index |
| Denominator | n/a |
| Proportion family households headed by single woman | |
| Source Table | B11001. Household Type (Including Living Alone) |
| Universe | Households |
| Numerator | [AF3J006] Family households: Other family: Female householder, no husband present |
| Denominator | [AF3J002] Family households |
| Proportion occupied housing units that are owner occupied | |
| Source Table | B25003. Tenure |
| Universe | Occupied housing units |
| Numerator | [AF7P002] Owner occupied |
| Denominator | [AF7P001] Total |
| Proportion African American | |
| Source Table | B02001. Race |
| Universe | Total population |
| Numerator | [AF2M003] Black or African American alone |
| Denominator | [AF2M001] Total |
| Proportion of adults who completed high school | |
| Source Table | B15003. Educational Attainment for the Population 25 Years and Over |
| Universe | Population 25 years and over |
| Numerator | [AF4O017] Regular high school diploma +[AF4O018] GED or alternative credential +[AF4O019] Some college, less than 1 year +[AF4O020] Some college, 1 or more years, no degree +[AF4O021] Associate’s degree +[AF4O022] Bachelor’s degree +[AF4O023] Master’s degree +[AF4O024] Professional school degree +[AF4O025] Doctorate degree |
| Denominator | [AF4O001] Total |
| Persons per square kilometer | |
| Source Table | B01003. Total Population |
| Universe | Total population |
| Numerator | [AF2L001] Total |
| Denominator | [ALAND] Current land area (2016 TIGER/Line census tracts shapefile) |
| Housing units per square kilometer | |
| Source Table | B25001. Housing Units |
| Universe | Housing units |
| Numerator | [AF7N001] Total |
| Denominator | [ALAND] Current land area (2016 TIGER/Line census tracts shapefile) |
