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A quota is a number of votes (obtained by formula) often relevant to deciding who wins and how ballots are evaluated or modified in proportional voting methods.
A quota is a number of votes (obtained by formula) often relevant to deciding who wins and how ballots are evaluated or modified in "[[proportional representation]]" voting methods]].


==[[W:Hare quota| Hare quota]]==
The two main quotas that will be described here are the "[[Hare quota]]" and the "[[Droop quota]]".
The Hare quota may be given as:


== Hare quota ==
:<math>\frac{\mbox{total} \; \mbox{votes}}{\mbox{total} \; \mbox{seats}}</math>
{{main|Hare quota}}


The "Hare quota" (also known as the "simple quota") is a formula used under some forms of the [[Single Transferable Vote]] (STV) system and the [[largest remainder method]] of [[party-list proportional representation]]. In these [[voting system]]s the quota is the minimum number of votes required for a party or candidate to capture a seat, and the Hare quota is the total number of votes divided by the number of seats.
Where:


The Hare quota is the simplest quota that can be used in elections held under the STV system. In an STV election a candidate who reaches the quota is elected while any votes a candidate receives above the quota are transferred to another candidate.
*<math>\text{total votes}</math> = the total valid poll; that is, the number of valid (unspoiled) votes cast in an election.
*<math>\text{total seats}</math> = the total number of seats to be filled in the election.


The Hare quota was devised by [[Thomas Hare]], one of the earliest supporters of STV. In 1868, [[Henry Richmond Droop]] (1831–1884) invented the [[Droop quota]] as an alternative to the Hare quota, and Droop is now widely used, the Hare quota today being rarely used with STV.
==[[W: Droop quota | Droop quota]==
Sources differ as to the exact formula for the Droop quota. As used in the Republic of Ireland the formula is usually written:


== Droop quota ==
<math >\left( \frac{\text{total valid poll}}{ \text{seats}+1 } \right) + 1</math>
{{main|Droop quota}}
The "Droop quota" is the quota most commonly used in elections held under the [[single transferable vote]] (STV) system. It is also sometimes used in elections held under the [[largest remainder method]] of [[party-list proportional representation]] (list PR). In an STV election the quota is the minimum number of votes a candidate must receive in order to be elected. Any votes a candidate receives above the quota are transferred to another candidate. The Droop quota was devised in 1868 by the English lawyer and mathematician [[Henry Richmond Droop]] (1831–1884) as a replacement for the earlier [[Hare quota]].


Today the Droop quota is used in almost all STV elections, including the forms of STV used in [[India]], the [[Republic of Ireland]], [[Northern Ireland]], [[Malta]] and [[Australia]], among other places. The Droop quota is very similar to the simpler "[[Hagenbach-Bischoff quota]]", which is also sometimes loosely referred to as the 'Droop quota'.
but more precisely


== References ==
<math >\operatorname{Integer} \left( \frac{\text{total valid poll}}{ \text{seats}+1 } \right) + 1</math>
<references/>


[[Category:Proportionality-related concepts]]
where:
[[Category:Quotas|*]]

* <math>\text{total valid poll}</math> = Total number of valid (unspoiled) votes cast in an election.
* <math>\text{seats}</math> = total number of seats to be filled in the election.
* <math>\operatorname{Integer}()</math> refers to the integer portion of the number, sometimes written as <math>\operatorname{floor}()</math>

Latest revision as of 01:41, 13 February 2024

A quota is a number of votes (obtained by formula) often relevant to deciding who wins and how ballots are evaluated or modified in "proportional representation" voting methods]].

The two main quotas that will be described here are the "Hare quota" and the "Droop quota".

Hare quota

The "Hare quota" (also known as the "simple quota") is a formula used under some forms of the Single Transferable Vote (STV) system and the largest remainder method of party-list proportional representation. In these voting systems the quota is the minimum number of votes required for a party or candidate to capture a seat, and the Hare quota is the total number of votes divided by the number of seats.

The Hare quota is the simplest quota that can be used in elections held under the STV system. In an STV election a candidate who reaches the quota is elected while any votes a candidate receives above the quota are transferred to another candidate.

The Hare quota was devised by Thomas Hare, one of the earliest supporters of STV. In 1868, Henry Richmond Droop (1831–1884) invented the Droop quota as an alternative to the Hare quota, and Droop is now widely used, the Hare quota today being rarely used with STV.

Droop quota

The "Droop quota" is the quota most commonly used in elections held under the single transferable vote (STV) system. It is also sometimes used in elections held under the largest remainder method of party-list proportional representation (list PR). In an STV election the quota is the minimum number of votes a candidate must receive in order to be elected. Any votes a candidate receives above the quota are transferred to another candidate. The Droop quota was devised in 1868 by the English lawyer and mathematician Henry Richmond Droop (1831–1884) as a replacement for the earlier Hare quota.

Today the Droop quota is used in almost all STV elections, including the forms of STV used in India, the Republic of Ireland, Northern Ireland, Malta and Australia, among other places. The Droop quota is very similar to the simpler "Hagenbach-Bischoff quota", which is also sometimes loosely referred to as the 'Droop quota'.

References