Wisconsin Legislative Technology Services Bureau - 2012-2020 Election Data with 2020 Wards

Description:

Election Data Attribute Field Definitions | Wisconsin Cities, Towns, & Villages Data Attributes 
Ward Data Overview:
July 2020 municipal wards were collected by LTSB
through the WISE-Decade system.  Current statutes require each county
clerk, or board of election commissioners, no later than January 15 and July 15
of each year, to transmit to the LTSB, in an electronic format (approved by
LTSB), a report confirming the boundaries of each municipality, ward and
supervisory district within the county as of the preceding “snapshot” date of
January 1 or July 1 respectively. Population totals for 2011 wards are carried
over to the 2020 dataset for existing wards. New wards created since 2011 due
to annexations, detachments, and incorporation are allocated population from
Census 2010 collection blocks. LTSB has topologically integrated the data, but
there may still be errors.
Election Data Overview:

The 2012-2020 Wisconsin election data that is included in this
file was collected by LTSB from the *Wisconsin Elections Commission (WEC) after
each general election. A disaggregation process was performed on this election
data based on the municipal ward layer that was available at the time of the
election. 
Disaggregation of Election Data:

Election data is first disaggregated from reporting units to
wards, and then to census blocks. Next, the election data is aggregated back up
to wards, municipalities, and counties. The disaggregation of election data to
census blocks is done based on total population. 

Detailed Methodology:

Data
is disaggregated first from reporting unit (i.e. multiple wards) to the
ward level proportionate to the population of that ward. 
The
data then is distributed down to the block level, again based on total
population. 
When
data is disaggregated to block or ward, we restrain vote totals not to
exceed population 18 numbers, unless absolutely required.

This methodology results in the following: 

Election
data totals reported to the WEC at the state, county, municipal and
reporting unit level should match the disaggregated election data total at
the same levels. 
Election
data totals reported to the WEC at ward level may not match the ward
totals in the disaggregated election data file. 
Some
wards may have more election data allocated than voter age population.
This will occur if a change to the geography results in more voters than
the 2010 historical population limits.

Other things of note…

We use a static, official ward layer (in this case created in
2020) to disaggregate election data to blocks. Using this ward layer creates
some challenges. New wards are created every year due to annexations and
incorporations. When these new wards are reported with election data, an issue
arises wherein election data is being reported for wards that do not exist in
our official ward layer. For example, if Cityville has four wards in the
official ward layer, the election data may be reported for five wards,
including a new ward from an annexation. 

There are two different scenarios and courses of action to these
issues: 

When
a single new ward is present in the election data but there is no ward
geometry present in the official ward layer, the votes attributed to this
new ward are distributed to all the other wards in the municipality based
on population percentage. Distributing based on population percentage
means that the proportion of the population of the municipality will
receive that same proportion of votes from the new ward. In the example of
Cityville explained above, the fifth ward may have five votes reported,
but since there is no corresponding fifth ward in the official layer,
these five votes will be assigned to each of the other wards in Cityville
according the percentage of population.
Another
case is when a new ward is reported, but its votes are part of reporting
unit. In this case, the votes for the new ward are assigned to the other
wards in the reporting unit by population percentage; and not to wards in
the municipality as a whole. For example, Cityville’s ward 5 was given as
a reporting unit together with wards 1, 4, and 5. In this case, the votes
in ward five are assigned to wards 1 and 4 according to population
percentage. 

Outline Ward-by-Ward Election Results

The process of collecting election data and disaggregating to
municipal wards occurs after a general election, so disaggregation has occurred
with different ward layers and different population totals. We have outlined
(to the best of our knowledge) what layer and population totals were used to
produce these ward-by-ward election results.

Election
data disaggregates from WEC Reporting Unit -> Ward [Variant year
outlined below]

Elections
1990 – 2000: Wards 1991 (Census 1990 totals used for disaggregation)
Elections
2002 – 2010: Wards 2001 (Census 2000 totals used for disaggregation)
Elections
2012: Wards 2011 (Census 2010 totals used for disaggregation)
Elections
2014 – 2016: Wards 2018 (Census 2010 totals used for disaggregation)
Elections
2018: Wards 2018Elections 2020: Wards 2020

Blocks
2011 -> Centroid geometry and spatially joined with Wards [All
Versions]

Each
Block has an assignment to each of the ward versions outlined above
In
the event that a ward exists now in which no block exists (occurred with
spring 2020) due to annexations, a block centroid was created with a
population 0, and encoded with the proper Census IDs.

Wards
[All Versions] disaggregate -> Blocks 2011

This
yields a block centroid layer that contains all elections from 1990 to
2018

Blocks
2011 [with all election data] -> Wards 2020 (then MCD 2020, and County
2020) 

All
election data (including later elections) is aggregated to
the Wards 2020 assignment of the blocks

Notes:

Population
of municipal wards 1991, 2001 and 2011 used for disaggregation were
determined by their respective Census.
Population
and Election data will be contained within a county boundary. This means
that even though MCD and ward boundaries vary greatly between versions of
the wards, county boundaries have stayed the same, so data should total
within a county the same between wards 2011 and wards 2020.
Election
data may be different for the same legislative district, for the same
election, due to changes in the wards from 2011 and 2020. This is due to
boundary corrections in the data from 2011 to 2020, and annexations, where
a block may have been reassigned.

*WEC replaced the previous Government Accountability Board (GAB)
in 2016, which replaced the previous State Elections Board in 2008. This dataset was automatically cataloged from the creator's Open Data Portal. In some cases, publication year and bounding coordinates shown here may be incorrect. Additional download formats may be available on the author's website. Please check the 'More details at' link for additional information.

Resource Link:

https://data-ltsb.opendata.arcgis.com/datasets/LTSB::2012-2020-election-data-with-2020-wards

Identifier:

https://www.arcgis.com/home/item.html?id=b411164fe264496c8b1a1b5c5d0c0b8d&sublayer=0

Language:

English

Creator:

Wisconsin State Legislature

Provider:

American Geographical Society Library – UWM Libraries

Resource Class:

Datasets

Resource Type:

Digital maps

Temporal Coverage:

Issued 2020

Date Issued:

2020-08-28

Spatial Coverage:

Wisconsin and United States

Rights:

Although this data is being distributed by the American Geographical Society Library at the University of Wisconsin-Milwaukee Libraries, no warranty expressed or implied is made by the University as to the accuracy of the data and related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the University in the use of this data, or related materials.

Access Rights:

Public

Format:

Shapefile