Glossary
Define the election, geography, demographic, data-quality, model, and product terms used throughout Akashic.
Akashic release
A coordinated version of code, data, and generated artifacts. Reproducible analysis should retain the release identifier or retrieval date when available.
American Community Survey (ACS)
A US Census Bureau survey published in annual one-year and five-year estimates. Akashic primarily uses documented ACS products appropriate to the geography. Every measure has a table, vintage, universe, and margin of error.
Citizen voting-age population (CVAP)
US citizens age 18 and older. CVAP is closer to the legally eligible electorate than total population or voting-age population, but it is not the same as registered voters or turnout.
County-equivalent
A Census-recognized unit treated like a county for statistical purposes, including certain independent cities, boroughs, parishes, and Connecticut planning regions.
Crosswalk
A documented mapping from one set of geographic identifiers or boundaries to another. Crosswalks may be exact or weighted and must identify the basis used.
Custom Place
A saved user-defined geography created in Places. It may contain multiple geographically separated components. Its data is rolled up from intersecting source units using the documented resolution.
Democratic or Republican margin
The difference between Democratic and Republican vote share, usually expressed in percentage points. D+5 means the Democratic candidate led by five points; R+5 means the Republican candidate led by five points.
Evidence level
The class of verification supporting a document or claim: production observation, runtime/control-plane observation, current repository evidence, unmerged pull request, or another maintained document.
Exact rollup
A value produced by summing complete constituent units without allocation. Exact rollup does not necessarily mean the boundaries are historically unchanged.
FIPS
Federal Information Processing Series geographic code. County records commonly use a five-digit state-plus-county FIPS code.
Geography tier
A family of comparable geographic units, such as county, state, congressional district, CBSA, DMA, or city.
Margin of error
The uncertainty published with a survey estimate. A displayed ACS estimate should not be interpreted as exact merely because the interface rounds it neatly.
Native result
A result reported by the source at the same geographic unit represented by the record.
Null
A field that belongs to the schema but has no available value for the record. Null is not zero.
Percentage point
The arithmetic difference between two percentages. Moving from 40% to 45% is a five-percentage-point increase and a 12.5% relative increase.
Political Twin
A place with a similar voting trajectory under the documented similarity model. It is a descriptive match, not a claim of identical demographics or causes.
Precinct
A local election reporting or administration unit. Precinct boundaries and identifiers can change between elections and are not a stable national Census geography.
Provenance
The trace from a public figure back through Akashic's transformation, source geography, upstream dataset, vintage, and license.
Reconciled disaggregation
Allocation of a certified larger-unit total across smaller geography using documented evidence, followed by adjustment so the smaller values sum exactly to the authoritative parent total.
Resolution
The geographic/methodological basis of a rollup, such as exact county aggregation or reconciled block-group allocation.
Swing
The change in margin between two elections. A place can swing toward a party while still being won by the other party.
Two-party vote
Democratic plus Republican votes, excluding other candidates. A two-party percentage or margin is not the same as a percentage of all ballots cast.
Universe
The population included in a survey measure's denominator, such as all people, people age 5+, adults age 25+, households, or citizen voting-age population.
Vintage
The reference year or release period of a dataset or boundary file. Two measures with the same retrieval date can have different vintages.