220 likes | 333 Views
Midwest Mapping Project: Ohio. Michael McDonald George Mason University. Supported by The Joyce Foundation. Talk Overview. Understanding the importance of census geography Lessons learned The mapping project Lessons learned. What is a Census Block?. Block 001. Block 002.
E N D
Midwest Mapping Project:Ohio Michael McDonald George Mason University Supported by The Joyce Foundation
Talk Overview • Understanding the importance of census geography • Lessons learned • The mapping project • Lessons learned
What is a Census Block? Block 001 Block 002
What is a Census Block? Columbus, Ohio
What is a Census Place? Columbus, Ohio
How to Draw Grid Districts Ohio Counties & Census Places
How to Draw Grid Districts Example Congressional Grid Plan
How to Draw Grid Districts Example Congressional Grid Plan
How to Draw Grid Districts Example Lower House Grid Plan
Important Lessons • Equal population districts must be of unequal geographic size; urban districts must be smaller than rural districts • Nicely-shaped districts are difficult to draw using census blocks; and may conflict with respecting existing political boundaries • Different approaches may be necessary to draw congressional and state legislative districts
The Mapping Project • Three mappers drew one plan for Congress and both state legislative chambers for each of these four types of plans: • Grid Districts • Compact Districts • Respect County Boundaries • Respect Census Place (City) Boundaries • These test plans are almost certainly not the absolute best that may be achieved • 2000 Census and Election Data used to evaluate plans • Legislative districts are not “nested”
The Mapping Project The full report is available at: http://elections.gmu.edu/Redistricting.html
Ohio Current Plans “Two-party vote” is the 2000 Presidential vote for the two major party candidates: Super = greater than 80% Strong = 80% to 55% Lean = 55% to 50% “Bias” is the number of Democratic majority seats minus the statewide two-party vote. A negative value indicates a pro-Republican plan. Majority Black or Hispanic districts have greater than 50% minority Voting Age Population.
Congressional Test Plans “Two-party vote” is the 2000 Presidential vote for the two major party candidates: Super = greater than 80% Strong = 80% to 55% Lean = 55% to 50% “Bias” is the number of Democratic majority seats minus the statewide two-party vote. A negative value indicates a pro-Republican plan. • Majority Black or Hispanic districts have greater than 50% minority Voting Age Population. Averages for three test plans presented.
State Senate Test Plans “Two-party vote” is the 2000 Presidential vote for the two major party candidates: Super = greater than 80% Strong = 80% to 55% Lean = 55% to 50% “Bias” is the number of Democratic majority seats minus the statewide two-party vote. A negative value indicates a pro-Republican plan. • Majority Black or Hispanic districts have greater than 50% minority Voting Age Population. • Averages for three test plans presented.
State House Test Plans “Two-party vote” is the 2000 Presidential vote for the two major party candidates: Super = greater than 80% Strong = 80% to 55% Lean = 55% to 50% “Bias” is the number of Democratic majority seats minus the statewide two-party vote. A negative value indicates a pro-Republican plan. • Majority Black or Hispanic districts have greater than 50% minority Voting Age Population. • Averages for three test plans presented.
Important Lesson: Race • Some test plans have fewer minority-majority districts thanthe current plans. Geographic criteria may be in conflict with the Voting Rights Act. • However, some test plans have more minority-majority districts.
Current Districts and Race OhioLower House Districts Racial Composition Darkest color is > 80% Black Voting-Age Population, Second darkest is 60-80%
Important Lessons: Politics • The Republicans tend to be advantaged in every test plan. • The test plans tend to have more competitive districts.
Why Geographic Criteria Tend to Benefit Republicans Ohio Partisan Composition 2000 Two-Party Vote, Blue = Democrat, Red = Republican
Why Geographic Criteria Benefit Republicans • Democrats are inefficiently concentrated within Cincinnati and Cleveland areas. • These metropolitan areas are located on the state border, effectively shutting off a direction to draw districts. • Conversely, Republicans are intermixed with Democrats in suburban and rural areas. • House districts tend to have the most bias, as these smaller districts tend to further concentrate Democrats in Akron, Dayton, and Columbus.
Important Lessons • Redistricting criteria can have predictable partisan and racial effects • If goals like partisan fairness or competition are desired, they should be codified into law, just as we do with minority representation goals described in the Voting Rights Act