Proportional elections mean that candidates are elected on winning an equal share of votes. This implies there has to be an order of electing the candidates. Either the voters get an order of choice (ranked ballot/preference vote) or only the parties decide the order on their exclusive party lists.  Party lists and their MMP hybrids are the oligarchic PR that has side-lined democratic PR that originally offered order in the vote and proportion in the count (the quota-preferential method or Single Transferable Vote).
Google: ERRE>Work>Electoral Reform>Briefs) namely,  BC Citizens Assembly on Electoral Reform (September 23).
Richard Lung. 
Website: Democracy Science; with links to 3 free e-books on election method: Peace-making Power-sharing; Scientific Method of Elections; Science is Ethics as Electics.