RubyVote: Election Methods Library in Ruby
-===========================================
+=============================================
-:Author: Benjamin Mako Hill
-:Copyright: MIT Media Lab and MIT
-:License: GNU GPL
+.. Caution::
-Summary
---------
+ This software is pre release software. The authors of this software
+ are neither expert Ruby programmers or elections in election
+ methods. We are hackers and enthusiasts in both. This software has
+ bugs and it's quite possible that is has bugs that may skew
+ results. If you understand Ruby or election methods, please audit
+ the code.
+
+Overview
+---------
+
+**Latest Version:** 0.2
+
+**Download Latest Version:** `here
+<http://rubyforge.org/projects/rubyvote>`__
+
+`RubyVote` is an election methods library implemented in Ruby. It is
+designed to make it very easy to implement a variety of different types
+of elections in Ruby including relatively complex election methods like
+Condorcet. It could be useful for any sort of election, poll, or
+decision making.
+
+New Versions
+*************
+
+`RubyVote` is graciously hosted by `RubyForge
+<http://rubyforge.org/>`__.
+
+You can visit the `RubyVote` homepage (a version of this file) here:
+
+ http://rubyvote.rubyforge.org/
-**Version:** 0.1
+You can visit the RubyForge project page to download the latest
+version of software, get access to the latest development version from
+Subversion, to file or bug, to look through documentation, to
+participate in the forums, or to contribute in other ways. That page
+is here:
-This software includes an set of classes to tally votes and compute
-winners in elections or votes using a series of different
-methods. Currrently these include:
+ http://rubyforge.org/projects/rubyvote
-* Plurality or "winner-take-all"
-* Approval
-* Borda
-* Simple Condorcet
-* Condorcet with Cloneproof SSD
-More information can be found at the following pages:
+More Information
+*****************
-* http://en.wikipedia.org/wiki/Plurality_electoral_system
-* http://en.wikipedia.org/wiki/Approval_voting
-* http://en.wikipedia.org/wiki/Borda_count
-* http://en.wikipedia.org/wiki/Condorcet_method
-* http://en.wikipedia.org/wiki/Shulze_method
+`RubyVote` is a library -- not an application or a voting machine. It
+simply takes the raw "tallies" of votes and computes the results.
+Currently, it does not include any sample interfaces (although if
+contributed, these may be included).
-Writing support for a new module (e.g., instant runnof voting) is a
-fantastic way to to contribute to this module.
+`RubyVote` current includes a set of classes to tally votes and compute
+winners in elections or votes using a series of different methods.
+Currently these include:
-This software is prerelease software. I am both a relatively new Ruby
-progreammming and relatively new to election methods. These election
-methods have bugs and may have bugs that skew results. If you are
-understand Ruby and election methods, please do me a favor and audit
-my code.
+* `Plurality`__ or "winner-take-all"
+* `Approval`__
+* `Borda`__
+* `Simple Condorcet`__
+* `Condorcet with Cloneproof SSD`__
+* `Instant Runnoff Voting`__ (Thanks Alexis Darrasse!)
+__ http://en.wikipedia.org/wiki/Plurality_electoral_system
+__ http://en.wikipedia.org/wiki/Approval_voting
+__ http://en.wikipedia.org/wiki/Borda_count
+__ http://en.wikipedia.org/wiki/Condorcet_method
+__ http://en.wikipedia.org/wiki/Schulze_method
+__ http://en.wikipedia.org/wiki/Instant_Runoff_Voting
+Writing support for a currently unsupported voting method is a fantastic
+way to to contribute to this module.
How To Use This Library
-------------------------
object upon creation or pass votes in one at at a time.
-.. Note:: *You* are responsible for ensuring that the votes are in
- correct form before you hand them to this module. This will
- not currently check for most types of invalid votes and does
- not (currently) accept a list of candidates at creation from
- which it checks all votes. As such, new candidates will be
- created when seen. If you think this is a meaningful
- addition to this library, please send a patch. Otherwise,
- please check for the validity of votes BEFORE you pass them
- to this election module.
+.. Note::
+
+ *You* are responsible for ensuring that the votes are in correct
+ form before you hand them to this module. This will not currently
+ check for most types of invalid votes and does not (currently)
+ accept a list of candidates at creation from which it checks all
+ votes. As such, new candidates will be created when seen. If you
+ think this is a meaningful addition to this library, please send a
+ patch. Otherwise, please check for the validity of votes BEFORE you
+ pass them to this election module.
Examples of each type of election currently supported can be seen in
the test.rb file distributed in this archive.
vote_array = [ ["A", "B"], ["B", "A"], ["B", "A"] ]
resultobject = CloneproofSSDVote.new(vote_array).result
+Instant Runnoff Voting (IRV)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+IRV is a preferential voting system used widely for government elections
+in Australia and New Zealand and elsewhere. IRV asks voters to rank
+candidates in preference and then holds a series of "runoff" elections
+by eliminating the weakest candidate and recomputing the election
+results until there exists a candidate who has a majority of the
+remaining votes.
+
+Example::
+
+ require 'runoff'
+ vote_array = [ ["A", "B"], ["B", "A"], ["B", "A"] ]
+ resultobject = InstantRunoffVote.new(vote_array).result
+
+
ElectionResult Objects
***********************
Each election result object will have the following methods:
-* #winner? -- return boolean as to the winner or winners of an election
+* #winner? -- return Boolean as to the winner or winners of an election
* #winners -- an array of winners of the election
* #ranked_candidates -- (where available) a list of ranked candidates
working at the MIT Media Lab. Please feel free to contribute to this
module and get your name added here.
-For more information about Mako and his programs, you can seee his
+For more information about Mako and his programs, you can see his
homepage here:
http://mako.cc
projects / rubyvote / blobdiff