Sequential proportional score voting (SPSV) is an Cardinal voting system that extends the concepts of Sequential proportional approval voting to Score voting ballots using the Kotze-Pereira transformation. For this reason, it is often referred to as SPAV + KP. It is one of the three extensions of SPAV to score ballots along with Reweighted Range Voting and Single distributed vote. It is the sequential version of Harmonic Voting.
Voters cast ballots by rating all candidates on a scale such as 0 to 5, where a blank rating is interpreted as the minimum value. Each rated ballot is converted into five virtual approval ballots using the KP transform.
Once this is done, SPAV is run on the virtual approval ballots to determine which candidates are elected. Each virtual ballot starts off with a weight of 1. For each seat, the candidate with the most weighted approvals is elected, and every virtual ballot is given a weight of 1/(1 + m), where m is the number of candidates approved on the ballot who have already been elected.