The Member Ideology data export contains biographical and ideological information about members of congress for the chamber(s) and congress(es) that were selected.
Quick Link (all congresses, all chambers, CSV format): https://voteview.com/static/data/out/members/HSall_members.csv
1+. The number of
the congress that this member’s row refers to. e.g. 115 for
the 115th Congress (2017-2019)House, Senate,
or President. The chamber in which the member served.1-99999. This is an ID
code which identifies the member in question. In general, each member
receives a single ICPSR identifier applicable to their entire career. A
small number of members have received more than one: this can occur for
members who have switched parties; as well as members who subsequently
become president. Creating a new identifier allows a new NOMINATE
estimate to be produced for separate appearances of a member in
different roles.0-99. Identifier
for the state represented by the member.0-99.
Identifier for the district that the member represents within their
state (e.g. 3 for the Alabama 3rd Congressional District).
Senate members are given district_code 0. Members who
represent historical “at-large” districts are assigned 99,
98, or 1 in various circumstances.MO for Missouri).1-9999.
Identifying code for the member’s party. Please see documentation for Party Data for
more information about which party_code identifiers refer
to which parties.1+. ICPSR occupancy
code. This item is considered legacy or incomplete information and has
not been verified. In general, members receive 0 if they
are the only occupant, 1 if they are the first occupant,
2 if they are the second occupant, etc.1-5. ICPSR
Attain-Office Code. This is an indicator that reflects the member’s last
means of attaining office. This item is considered legacy or incomplete
information and has not been verified. Members received 1
if they were elected in a general election, 2 if elected by
special election, 3 if directly elected by a state
legislature, and 5 if appointed.0-1. A
1 indicates NOMINATE was estimated conditionally for a
given member. 0 otherwise. Conditional estimation implies
that an estimate is provisional and subject to updates when the next
full estimation of NOMINATE scores occurs.We present two main estimates of a legislator’s ideology: NOMINATE
and Nokken-Poole. NOMINATE estimates assume that members occupy a static
ideological position across the course of their career. Nokken-Poole
estimates assume that each congress is completely separate for the
purposes of estimating a member’s ideology. We expect that most users of
our data will primarily make use of the nominate_dim1
field, which reports the first dimension (often interpreted as economic
liberalism-conservatism) of members as estimated by NOMINATE.
For more information on these scores, please see discussion in our journal article:
Boche, Adam, Jeffrey B. Lewis, Aaron Rudkin, and Luke Sonnet. “The new Voteview.com: preserving and continuing Keith Poole’s infrastructure for scholars, students and observers of Congress”. Public Choice 176(1-2). Available online: https://link.springer.com/article/10.1007/s11127-018-0546-0
To cite this data, please use the following citation:
Lewis, Jeffrey B., Keith Poole, Howard Rosenthal, Adam Boche, Aaron Rudkin, and Luke Sonnet (2026). Voteview: Congressional Roll-Call Votes Database. https://voteview.com/