Quota

From Electowiki
Jump to navigation Jump to search

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.

Hare quota[edit | edit source]

The Hare quota may be given as:

Where:

  • = the total valid poll; that is, the number of valid (unspoiled) votes cast in an election.
  • = the total number of seats to be filled in the election.

Droop quota[edit | edit source]

Sources differ as to the exact formula for the Droop quota. As used in the Republic of Ireland the formula is usually written:

but more precisely

where:

  • = Total number of valid (unspoiled) votes cast in an election.
  • = total number of seats to be filled in the election.
  • refers to the integer portion of the number, sometimes written as

One reason Droop quotas are used more often than Hare Quotas for ranked PR methods is because not only do they often help reduce the amount of vote-counting necessary, but they almost entirely eliminate the possibility of a majority of voters receiving a minority of seats compared to Hare Quotas. The Droop Quota is the smallest possible quota that guarantees that there will be as many quotas as there are winners desired.

Hagenbach-Bischoff Quota[edit | edit source]

The Hagenbach-Bischoff Quota (known by a few other names as well) is unambiguously (total valid poll/seats + 1) or Integer(total valid poll/seats + 1). Some sources call the HB Quota a Droop Quota instead, though nobody considers the definitions given for a Droop Quota above to be a HB Quota. It is possible to have more quotas than winners desired using the HB Quota, in which case it will usually be necessary to break at least one tie between various candidates to decide who should win.