Part 1:The Mathematics Behind Ireland’s PR Voting System: How the Count Begins

Understanding Ireland’s PR–STV Voting System

Ireland uses PR–STV, or Proportional Representation by the Single Transferable Vote, for elections. This video explains how the system works in clear, accessible language.

It covers:

how voters rank candidates using 1, 2, 3, and so on
the difference between valid, invalid, and non-transferable votes
how the quota is calculated
what happens when candidates are eliminated
how votes transfer to the next available continuing candidate
how surplus votes are distributed
what transfer values mean
why a candidate may sometimes be elected without reaching the quota

A key point in PR–STV is that a vote does not stop simply because the voter’s second preference has already been eliminated. It moves to the next available candidate still in the race, provided the voter has marked one.

This video is based on an explanatory paper by Dr Cora M. Stack,

Disclaimer: This video is for educational purposes only. The views expressed are those of the author and do not represent the views of any institution.

Видео Part 1:The Mathematics Behind Ireland’s PR Voting System: How the Count Begins канала Dr Cora Stack