Data & methodology
Where the data comes from, what it covers, and how each derived measure is computed.
Sources
- Data sourcesConceptWhere CapitolMath's bills, votes and legislators come from, and how often they're refreshed.
- Coverage by jurisdictionReferenceHow many bills CapitolMath holds for each state and Congress, which sessions, how recent, and whose calendar it carries.
- AmendmentsConceptWhat an amendment to a bill is, and how CapitolMath adds amendment records legislature by legislature, each once its records have been checked.
Measures
- Political lean scoringConceptHow a bill's economic and social lean is scored, and how a legislator's is worked out from their votes and sponsorships.
- Effective datesConceptWhen an enacted law takes effect, how CapitolMath works it out from the enacted text and each state's rules, and how its accuracy is checked.
- Legislative velocityConceptWhether a bill is moving faster or slower than its legislature's calendar, and where it sped up or stalled.
- Bipartisan and popularity indicesConceptHow evenly a bill's last floor vote split across parties, and how many voted for it.
- Whip countsConceptHow a bill's next floor vote is projected member by member, how to read the projection, and how its accuracy is checked.