L-Lists Logo L-Lists logo (words)
The collaborative list making website by
StatisticalConsultants Ltd
Search for lists:
Follow L-Lists:
Also by Statistical Consultants Ltd: Unlisted Videos - A website for unlisted YouTube videos.

List of Ranked Preference Voting Methods


List started by: L-Lists
List contributors: L-Lists
Date started: 29 Sep 2014
Last updated: 29 Sep 2014
Keywords: politics, political science, democracy, voting, elections

Description:

A list of ranked preference voting methods, including instant runoff, Condorcet voting, and Borda count.






Row # Title Image Description
1 Instant Runoff Instant Runoff 
Instant runoff was developed by William Robert Ware around 1870, although similar methods had been developed earlier.

Instant runoff has the following steps:
1. Count the number of first choice votes each candidate gets.
2. If no candidate has more than half of the first choice votes, eliminate the candidate with the lowest number of first choice votes.
3. The voters who ranked that candidate first, have their ranked preferences brought forward i.e. their second choice becomes their first; their third choice becomes their second etc.
4. If no candidate has more than half of the first choice votes, return to step 1, but consider only the remaining candidates.

Assuming there isn't a tie, eventually there would be one remaining candidate with more than half of the first choice votes. That candidate is the winner.
2 Condorcet Voting Condorcet Voting 
Condorcet voting was outlined in a paper written in 1785 by the mathematician, philosopher and politician, Marie Jean Antoine Nicolas Caritat, Marquis de Condorcet. A similar method was divised by Ramon Llull in 1299.

Each voter's ranked preference is converted into a Condorcet matrix (also called a victory matrix or beat matrix). For example, if a voter ranks the candidates A (first) then C then B, they would have the following Condorcet matrix:

Condorcet matrix

Each cell in the matrix represents a single pair wise comparison between candidates. Reading from left to right, starting at the top left hand corner, the matrix can be interpreted as follows:
- 'Candidate A beats A' is false (0)
- 'Candidate A beats B' is true (1)
- 'Candidate A beats C' is true (1)
- 'Candidate B beats A' is false (0)
- and so on

If candidate row beats candidate column then a 1 is assigned. If not, then a 0 is assigned.

Once a Condorcet matrix been calculated for each voter, the matrices are then summed. For example, let's say there are three voters with the following individual level Condorcet matrices:

Condorcet matrices

Those three matrices are then added together:

aggregate Condorcet matrix

The Condorcet election winner is determined by the pairwise comparisons. If a candidate is preferred to all other candidates, they are the winner. If no such candidate exists, then there is a cyclical ambiguity and a resolution method must be used to determine the winner. Several resolution methods have been suggested, ranging from the simple Copeland method, to the advanced Schulze method.
3 Borda Count Borda Count Borda count voting was developed by Jean-Charles de Borda in 1770.

With Borda count, each vote would be converted into a set of Borda scores. Borda's proposed scoring method was that if there were k candidates, the candidate ranked first by the voter would receive a score of (k-1), the second (k-2) etc. If a voter's preferences are strictly transitive for all candidates, their least preferred candidate would receive a score of zero.

Once the Borda score set is determined for each voter, the Borda scores are added up for each candidate. The candidate with the highest Borda score is the winner.


Related Lists

List of Voting Systems
List of Executive Branch Government Systems



Add to this list

  • Each row in the following text fields represents one entry in the list.
  • Each list entry must have a title and/or URL. Entry descriptions and images are entirely optional.
  • The submitted link URLs would be automatically standardised. This will mean that it doesn't matter whether or not you include the https:// (or https//) at the beginning or a / at the end.
  • Don't worry if a title, URL or description takes more than one line in the input form.  Regardless of whether the input was entered manually or copied and pasted, this website can distinguish between whether the input going to a new line was due to its long length or from the use of the enter key.
  • New list entries are added to the bottom of the list. Chronologically ordered lists should be ordered from the earliest to the latest.
  • If an image is too wide or tall, it would be automatically scaled.

Email:
Password:
Not registered? Register here.


Link Titles Link URLs Link Descriptions




List Entry Image URLs




Report this list


Email:
Password:
Not registered? Register here.


Junk list Irrelevant or broken links
Spelling, grammatical or formatting errors Factual errors or opinionated descriptions
Out of date information Suggest related lists or alterations
Forbidden content/links Other


Message:




Receive Notifications

Receive notifications via email, whenever new list entries are added to this list.

Email:
Password:
Not registered? Register here.





Help - Terms of Usage - Privacy Policy - Contact
© Statistical Consultants Ltd 2012 -