Tag Archives: redistricting

Making & Using Custom 115th Congressional District Maps

.. using GIS resources to create custom 115th Congressional District maps .. use the methods, data and tools described in this section to develop custom congressional district maps. View patterns of economic prosperity by neighborhood for one or all congressional districts. Flexibly associate a congressional district boundary with related geography and subject matter.  See related Web section for more details.

Join the Congressional District-State Legislative District (CDSLD) Group .. be a part of the community. .. click here to join .. there is no cost.

Coming up … mapping/analyzing school district finances in context of the 115th Congressional Districts (June 2017).

See the related section on Making/Using 113th Congressional District Maps.
.. view different congressional district vintages in same map.

115th Congressional Districts by Incumbent Party Affiliation
This view and related GIS project/data update when changes are made to the 115th Congressional Districts incumbents (last updated 5/10/17). Party affiliation shown in this view is also available in the related interactive table. Click graphic for larger view. Expand browser window for best quality view.

– View developed using CV XE GIS and related GIS project.
– see below in this section about using this GIS project.

Use the Geographic Information System (GIS) tools and data to view/show congressional district in context with roads, landmarks and other geography. Flexibly add labels. Create pattern views. Add your own data.

Patterns of Economic Prosperity by 115th Congressional District
The following graphic shows patterns of ACS 2015 median household income (MHI) by 115th Congressional District. Click graphic for larger view. Expand browser window for best quality view.

– View developed using CV XE GIS and related GIS project.
– use the GIS project and tools see below to create different views.

Examine Characteristics of any Congressional District
The following graphic shows patterns of ACS 2015 median household income (MHI) by census tract in context of 115th Congressional Districts in a region of North Carolina. CD 3712 (Charlotte area) is shown with bold boundary. It is easy to see which areas/tracts have different levels of economic prosperity.

– View developed using CV XE GIS and related GIS project.
– use the GIS project and tools see below to create different views; add other layers.

Creating congressional district maps is often specific to a particular analysis, zoom-view, labeling, combination of different geographies or other considerations. While there are no estimates of unemployment by congressional district, using GIS tools it is possible to view/geospatially analyze patterns of unemployment within congressional district by county, census tract, block group and other geography.

Join me in a Data Analytics Lab session to discuss more details about accessing and using wide-ranging demographic-economic data and data analytics. Learn more about using these data for areas and applications of interest.

About the Author
— Warren Glimpse is former senior Census Bureau statistician responsible for innovative data access and use operations. He is also the former associate director of the U.S. Office of Federal Statistical Policy and Standards for data access and use. He has more than 20 years of experience in the private sector developing data resources and tools for integration and analysis of geographic, demographic, economic and business data. Contact Warren. Join Warren on LinkedIn.

115th Congressional Districts: Analysis and Insights

.. interpretative data analytics; tools, data & methods ..  this section is focused on 115th Congressional District geographic, demographic and economic patterns and characteristics. Use tools and data reviewed here to examine/analyze characteristics of one congressional district (CD) or a group of CDs based on state, party or other attribute. Use the GIS resources described here for general CD reference/pattern/analytical views, to examine current demographics and demographic change and for redistricting applications. See this related Web section for more details.

Examining the 115th Congressional Districts
• the 115th Congress runs from January 2017 through December 2018.
• FL, MN, NC, VA have redistricted since the 114th CD vintage;
  .. some 115th CDs have new boundaries compared the 114th CDs.
• view, rank, compare CDs using the interactive table.
  .. table uses ACS 2015 data for 115th CDs & include incumbent attributes.
  .. examine districts by party affiliation.
• use these more detailed 114th CD interactive tables
  .. data based on 2015 American Community Survey – ACS 2015.
  .. corresponding data for the 115th CDs from ACS 2016 available Sept 2017.
• use the new GIS project including 114th & 115th CDs described below.
  .. create CD thematic and reference maps;
  .. examine CDs in context of other geography & subject matter.
• join us in the April 25 Data Analytics Lab session

Visual Analysis of Congressional Districts
The following views 1) provide insights into patterns among the 115th CDs and 2) illustrate how 114th to 115th geographic change can be examined. Use CV XE GIS software with the GIS project to create and examine alternative views.

Patterns of Household Income by 115th Congressional District
The following graphic shows the patterns of the median household income by 115th Congressional District based on the American Community Survey 2015 1-year estimates (ACS2015). The legend in the lower left shows data intervals and color/pattern assignment

.. view developed with ProximityOne CV XE GIS and related GIS project.

Charlotte NC-SC Metro Area
  – with 114th/115th Congressional District 12

The following graphic shows North Carolina CD 12 with 114th boundary (blue) and 115th boundary (pale yellow) and Charlotte metro bold brown boundary. Click graphic for larger view with more detail. Expand browser window for best view.

.. view developed using the CVGIS software.

• View zoom-in to Charlotte city & Mecklenburg County.

115th Congressional District Interactive Table
Use the interactive table to examine characteristics of one congressional district (CD) or a group of CDs. The following graphic illustrates use of the interactive table. First, the party type was selected, Democratic incumbents in this example. Next, the income and educational attainment columns were selected. Third, the set of districts were sorted on median household income. It is quick and easy to determine that CA18 has the highest median household income and that the MHI is $1,139,900. Try using the table to examine districts of interest.

Join me in a Data Analytics Lab session to discuss more details about accessing and using wide-ranging demographic-economic data and data analytics. Learn more about using these data for areas and applications of interest.

About the Author
— Warren Glimpse is former senior Census Bureau statistician responsible for innovative data access and use operations. He is also the former associate director of the U.S. Office of Federal Statistical Policy and Standards for data access and use. He has more than 20 years of experience in the private sector developing data resources and tools for integration and analysis of geographic, demographic, economic and business data. Contact Warren. Join Warren on LinkedIn.

Voting District Geography & Demographics

.. voting district, or election precinct, demographics are typically hard to acquire, making analysis of voting districts a challenging task. Voting district analysis is of interest for many reasons. Voting districts are the lowest common denominator for most election areas — from city council to the U.S. House of Representatives. This section illustrates how voting district (VTD) geography can be examined in context of other geography and how voting district demographics can be analyzed using GIS resources. These applications make use of Fairfax County, VA,
part of the Washington, DC metro, but can be developed for most counties/areas across the U.S.

Voting Districts & Neighborhood Patterns
The following view uses the Fairfax County GIS project to examine voting districts (black boundaries) in context of neighborhood economic prosperity. The current vintage VTD shapefile (213 VTDs) was obtained from the County. This view shows median household income by census tract. Using the GIS layer editor, different types of demographic-economic subject matter (such as educational attainment, housing value, language spoken at home …) could be used.

… Click graphic for larger view. View developed using CV XE GIS.

Voting District Scope and Vintages
As of Census 2010, there were 177,808 VTDs covering the U.S. While shapefiles for Census 2010 vintage VTDs are available as a part of the TIGER geographic database, most of these areas have now been updated owing to redistricting and the 2012 and 2014 elections. VTD boundaries can change frequently. While Census 2010 demographic data were tabulated for Census 2010 VTDs, these demographics of less interest to analyzing post-redistricting scenarios due to the changing VTD geography.

Voting District Drill-down Demographics
The following view uses the same Fairfax County GIS project to examine census block demographics by voting district. The graphic shows a zoom-in view focused on the Sherwood VTD in southeast Fairfax County. Using the CV XE GIS site analysis tool, all census blocks are selected within the Sherwood VTD (cross-hatched). A subset of blocks could have been selected to examine just part of the VTD. The table to the right of the map shows the aggregated total population and housing units for this VTD. As of Census 2010 there were 1,380 population in this VTD. Other demographic attributes, such as population by age, gender, or race/origin could be integrated into the shapefile using data sourced from Census 2010 Summary File 1.

… Click graphic for larger view. View developed using CV XE GIS.

There are 27 census blocks that comprise the Sherwood VTD. Using the View File button in the above operation, these 27 census block records can be viewed using the CV XE GIS dBrowser tool. A partial view of the records is shown below. This file can be exported for use with other software.

… Click graphic for larger view. View developed using CV XE GIS.

VTDs and Schools & School Attendance Zones
Using the GIS project, the attendance zone and schools layers can be checked/shown. School locations can be examined by VTD; VTDs intersecting attendance zones can be examined. What VTDs are relevant to which schools/attendance zones?  What is the demographic composition of these VTDs?  The following view shows high schools (red markers) and high school attendance zones (red boundaries).  Note in the legend to the left of map view, that different types of schools and attendance zones can be viewed in wide-ranging combinations. Other types of geography can be added to the mix such as voting districts.  The VTD/precincts layer is not shown in the following view so that the view of schools and attendance zones is not obstructed.  It can be added to the view by clicking the checkbox by the Precincts layer in the legend panel to the left of the map view.

… Click graphic for larger view. View developed using CV XE GIS.

VTDs and One Person, One Vote
In May 2015, the Supreme Court agreed to consider redefining ‘one-person, one-vote’ principle. See USATODAY story. How might this ruling impact election precinct geography?

Issues to be examined in upcoming sections include determining the size of the voting age population by VTD and the size of the citizen voting age population. These attributes could be examined at the block group level of geography, not reviewed here. See additional information on the citizen voting age population.

About the Author
— Warren Glimpse is former senior Census Bureau statistician responsible for innovative data access and use operations. He is also the former associate director of the U.S. Office of Federal Statistical Policy and Standards for data access and use. He has more than 20 years of experience in the private sector developing data resources and tools for integration and analysis of geographic, demographic, economic and business data. Contact Warren. Join Warren on LinkedIn.

Voting Rights Act Demographics

Examining patterns of the citizen voting age population … the Voting Rights Act prohibits development of voting districts that discriminate against potential voters on the basis of race and/or language minority status. To examine how voting districts comply with the Voting Rights Act requires data on the citizen voting age population (CVAP) by race/origin for small geographic areas. The ACS 2013 5-yearCVAP special tabulation (released February 2015) provides these estimates for census tracts and block groups (and higher level geography). See the related Web section for more detail.

The CVAP estimates provide only one part of the required data. The voting district boundaries and census block boundaries/demographics are also needed to be used in combination with the CVAP estimates. Using GIS tools, the CVAP estimates can be used in mapping applications, such as those reviewed in this section, in combination with voting district boundaries to reveal potential non-compliance in the structure of voting districts.

Use this interactive table in this section to view/rank/compare/query national scope citizen and CVAP estimates by race/ethnicity by census tract. See more about the ACS CVAP data.

Patterns of CVAP Hispanic Population by Neighborhood
The map presented below shows patterns of the Hispanic citizen voting age population as a percent of total population by census tract in the Los Angeles area. Percentage intervals by green color pattern are shown in legend at left of map. Congressional Districts are shown with dark blue boundaries and labeled with congressional district codes. It is easy to see where concentrations of percent Hispanic citizen voting age population are located and how the distribution relates to congressional districts.

Click graphic for larger view; view developed with CV XE GIS.
Map view developed using CVAP2013 GIS Project.

Patterns of CVAP Asian Alone Population by Neighborhood
The map presented below shows patterns of the Asian alone citizen voting age population as a percent of total population by census tract in the Los Angeles area. Percentage intervals are shown by blue color patterns are shown in legend at left of map. Congressional Districts are shown with dark blue boundaries and labeled with congressional district codes. It is easy to see where concentrations of percent Asian alone citizen voting age population are located and how the distribution relates to congressional districts.

Click graphic for larger view; view developed with CV XE GIS.
Map view developed using CVAP2013 GIS Project.

Examining Relationships Among Key Geography and Demographics
An upcoming post will review use of GIS tools examine the relationship between 1) census tracts and the CVAP data, 2) voting districts and 3) census blocks and census block demographics in more detail. That section will review use of downloadable GIS tools and resources that can be used to examine these geographic-demographic relationships in more detail. Voting Rights Act (VRA) stakeholders can better see how to use these data and tools to achieve VRA goals.

About the Author
— Warren Glimpse is former senior Census Bureau statistician responsible for innovative data access and use operations. He is also the former associate director of the U.S. Office of Federal Statistical Policy and Standards for data access and use. He is an expert in developing hard-to-estimate demographic estimates and projections. He has more than 20 years of experience in the private sector developing data resources and tools for integration and analysis of geographic, demographic, economic and business data.

Tracking Language Use and the Decennial Census

Since 1790, the decennial census has been arguably the single most important U.S. geographic-demographic-economic statistical data resource. Data from these decennial censuses are in daily widespread use for analysis and decision-making. The companion TIGER/Line digital map database is the underlying geographic database enabling most Web browser maps. The TIGER data helped spawn the development of Geographic Information Systems (GIS) and visual data analysis.

This section illustrates use of the New York Times Chronicle tool to track language use relating to the decennial census. The Chronicle tool can be used to visualize language use in the New York Times news coverage throughout its history. The following graphics show results of using the Chronicle tool. There are additional features of the tool not shown here, notably lists of accessible NYT stories. Click graphics for larger view.

Decennial Census — all references

Decennial Census — 1960 through 2010

More about Census 2010

Redistricting – Reapportionment — a basic reason for the decennial census

More about congressional districtsstate legislative districts

Asian – Hispanic — race/origin; decennial census is source of most detailed data on these topics

More about Asian populationHispanic population

Integration – Segregation – Diversity — topics making widespread use of decennial census data

More about neighborhood diversityUSATODAY diversity analyses

American Community Survey — “rolling annual census” introduced in 2004

More about ACS 2013

Exactly how the decennial census has been used in stories cannot be effectively determined using the Chronicle tool. The decennial census lead-up and process of conducting and tabulation data is the basis of many stories. The use of decennial census data is yet another basis for stories.

About the Author
— Warren Glimpse is former senior Census Bureau statistician responsible for innovative data access and use operations. He is also the former associate director of the U.S. Office of Federal Statistical Policy and Standards for data access and use. He has more than 20 years of experience in the private sector developing data resources and tools for integration and analysis of geographic, demographic, economic and business data.