Group Decision - Secure Transparent Online Electoral Process
Voting Systems
Preferential Voting ( IRV, STV, Hare-Clark)

Description:  You (the election coordinator) choose the options to vote on.

The voters then preferences these options in order from 1 to 'n' in order of priority (where 'n' is the total number of options available).

A number 1 indicates a primary preference (the most prefered).

The counting process involves Eliminating and Electing (if more than one option is to be chosen) options using a Quota (proportion of total votes).

The counting procedure for a Quota Preferencial Election is quite complex, and basically you need to know that when your vote is transferred it does so at its full value, unless it has been used to 'help' elect a candidate, in which case only the 'value not used' is transferred to the next prefered candidate.

  • When a single option is being chosen this is also called Instant Runoff Voting (IRV).

  • When more than one option is to be chosen this is also referred to as Single Transferrable Voting (STV), or more fully "Quota Preferential Proportional Representation."

  • When specifically 7 options are chosen (quota of 12.5%) then this is the true Hare-Clark Proportional system.

Commentary:  Whilst quite complex, this system is mathematically very fair, and only rivaled by the condocet methods.

It allows for a clear "positive" and "negative" voting effect.

One of the premises of the system is that it is VERY mathematically fair. Especially when more than one candidate (option) is being chosen. Indeed some would argue that the fairness of the system is simply becuase more than 1 person IS being chosen (ie its proportional).

The orignal design even stipulates that the optimum number of options to elect should be an odd number around 7. This gives a quota of just over 12.5%. This is high enough that silly or extreme options are not going to end up being elected. It is also low enough to ensure that significant minority opinions can be accurately represented.

History:  Developed by two mathematicians, Herr and Clarke, this is often referred to as the Herr-Clarke system. In its purest form it is used in the republic of Ireland, Malta and the state of Tasmania in Australia (representing the largest examples of QPPR elections)


External Links:  wiki - Single_Transferable_Vote

Proportional Representation Society of Australia