STV Basics: 19 MCQs with answers

To achieve proportional representation in multi-member districts

STV is designed to produce proportional representation in multi-member districts by electing multiple representatives who reflect the diversity of voter preferences.

Rank candidates in order of preference

STV uses a preferential ballot where voters rank candidates (1, 2, 3, etc.) to indicate their order of choice.

The movement of surplus and eliminated candidates' votes to other candidates

The 'transferable' aspect means that votes are not locked to a candidate; they can be transferred to other candidates based on voters' preferences, ensuring broader representation.

Proportional representation

STV is a proportional representation system because it aims to allocate seats in proportion to votes, unlike plurality systems.

True

Yes, any candidate who reaches the quota is elected in that round.

False

STV is primarily a multi-winner system, though it can be used for single-winner elections (as IRV).

The minimum number of votes a candidate needs to be elected

The quota is the minimum number of votes required for a candidate to be elected. The most common formula is the Droop quota: (total valid votes / (seats + 1)) + 1.

They are transferred to remaining candidates according to voters' next preferences

Surplus votes (votes above the quota) are transferred to other candidates based on the next available preference on each ballot, ensuring votes are not wasted.

They are transferred to the remaining candidates based on next preferences

When a candidate is eliminated (usually the one with the fewest votes), their ballots are transferred to the next preferred candidate still in the race.

It minimizes wasted votes and produces proportional outcomes

STV reduces wasted votes by transferring preferences and helps achieve proportional representation, allowing minority groups to gain representation.

It can be complex to count and may lead to lengthy vote counts

STV counting is more complex than plurality or party-list systems, often requiring multiple rounds and computer assistance, which can delay results.

Ireland

Ireland uses STV for its Dáil (lower house) elections. Australia uses it for the Senate, but Ireland is a prominent national example.

The number of votes a candidate receives beyond the quota

A surplus occurs when a candidate receives more votes than the quota. These surplus votes are transferred to other candidates to avoid wasting them.

Combine all parties' votes into a national pool

STV operates within individual multi-member districts; it does not pool votes nationally. Counting is done district by district.

It encourages multi-party systems and coalition building

Because STV is proportional, smaller parties have a better chance of winning seats, often leading to a multi-party system and coalition governments.

The candidate with the fewest votes is eliminated and their votes transferred

If seats remain unfilled, the candidate with the fewest votes is eliminated, and their votes are transferred to other candidates. This process repeats until all seats are filled.

Voters may find ranking many candidates confusing

In STV, voters may need to rank many candidates, which can be overwhelming, especially in large districts with many candidates.

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

The Droop quota is the most common quota in STV. It is calculated as floor(Total valid votes / (Seats + 1)) + 1, ensuring that no more candidates can reach the quota than there are seats.

STV can be used for both single-winner and multi-winner elections

STV is a multi-winner system, but when used with a single winner, it is identical to instant-runoff voting (IRV). Thus, STV can be adapted for single-winner contests.