electoral system
| districts
| type
| description
|
first-past-the-post (FPTP) |
single-member |
plurality |
The candidate that obtains more votes than any other is elected, even if that person only won a minority of votes cast |
two-round system (TRS) |
single-member |
majority |
A runoff election is held between the two top vote-getters, in order to ensure that the winner obtains a majority of votes cast |
alternative vote (AV), or instant runoff |
single-member |
majority |
Voters indicate an order of preference among candidates. If no candidate obtains a majority outright, the last-place candidate is removed, and the associated second-choice votes are added to the totals of the remaining candidates. The process is repeated until a candidate secures a majority. |
block vote (BV) |
multiple-member |
plurality |
Voters may cast as many votes as there are open seats. If there are n seats to be filled, the top n vote-getters are elected |
single non-transferable vote (SNTV) |
multiple-member |
semi-proportional |
Voters can only cast a single vote among candidates for n seats. The top n vote-getters are elected. |
single transferable vote (STV), also known as preference or choice voting |
multiple-member |
proportional |
Voters indicate an order of preference among candidates. Candidates whose first-choice vote totals attain the Hare Quota—(votes cast/n+1) + 1— are elected. The last-place candidate is removed, and the associated second-choice votes are added to the totals of the remaining candidates. The process is repeated until all n seats are filled. |
mixed member proportional (MMP) |
mixed |
proportional |
The legislature consists of a block of seats that are elected by plurality or majority from single-member districts, and another block of seats that are elected in multi-member districts under a proportional system. The proportional seats are awarded in such a way as to compensate for disproportional effects in the single-member district outcomes. |
parallel |
mixed |
semi-proportional |
The legislature consists of a block of seats that are elected by plurality or majority from single-member districts, and another block of seats that are elected in multi-member districts under a proportional system. The proportional seats are awarded independently of the outcomes in single-member districts. |
party list |
multiple-member |
proportional |
Voters choose from among party lists, and seats are awarded in proportion to the vote received by each party. Candidates are seated in the order listed. |