STV Basics: 18 MCQs with answers

To achieve proportional representation in multi-member districts

STV is designed to produce proportional representation, meaning the number of seats a party wins roughly matches its share of the vote, especially in multi-member districts.

Voters to indicate a backup choice if their first choice is eliminated or has surplus votes

Ranking lets voters show not only their first choice but also subsequent preferences, which are used to transfer votes when a candidate is eliminated or has more votes than needed to win.

It minimizes wasted votes and allows for proportional representation

STV reduces wasted votes because votes for losing candidates or surplus votes are transferred, and it produces proportional outcomes.

A list of candidates to be ranked in order of preference

STV ballots require voters to rank candidates numerically (1, 2, 3, etc.) according to their preference.

Their votes are transferred to the remaining candidates based on next preferences

When a candidate is eliminated, each of their ballots is transferred to the next-ranked candidate who is still in the race.

Local council elections in multi-member wards

STV is often used for local council elections where multiple representatives are elected from a single ward, such as in Scotland and some U.S. cities.

True

STV is designed to produce proportional outcomes, meaning the composition of the elected body reflects the proportion of votes each party or group receives.

False

In STV, voters rank individual candidates, not party lists. This is a key difference from list PR systems.

The minimum number of votes a candidate needs to be elected

The quota is the minimum number of votes a candidate must achieve to be elected. It is calculated based on the total valid votes and the number of seats to be filled.

(Total votes) / (Seats + 1) + 1

The Droop quota is commonly used: (Total valid votes) / (Seats + 1) + 1. This ensures that only the required number of candidates can reach the quota.

They are transferred to remaining candidates based on voters' next preferences

Surplus votes are transferred to other candidates according to the next preferences marked on those ballots, ensuring that votes are not wasted.

The candidate with the fewest votes is eliminated

If no one meets the quota, the candidate with the fewest votes is eliminated, and their votes are transferred to the next preferences on those ballots.

It is complex for voters to understand and for officials to count

STV can be more complex than first-past-the-post because voters must rank candidates and counting involves transfers and quotas.

Ireland

Ireland uses STV for its Dáil (lower house) elections, as well as for European and local elections.

Single-member districts

STV uses multi-member districts, not single-member districts, to achieve proportional representation.

To ensure that votes are not wasted

Transferring surplus votes ensures that as many votes as possible contribute to electing a candidate, minimizing wasted votes.

floor(Total votes / (Seats + 1)) + 1

The Droop quota is the smallest number that guarantees no more than the required number of candidates can reach it. It is calculated as the integer part of (Total votes / (Seats + 1)) plus one.

It becomes exhausted and is set aside

If a ballot has no more usable preferences (all ranked candidates are eliminated or elected), it is considered exhausted and no longer participates in the count.