kground">Basic background</h2>
<p>Before starting, you will frequently find the following concepts: alternative and voter. An <em>alternative</em> is the unit that we want to measure (its score), and the voter is the one who voted for alternatives. In general, the goal is to aggregate voters' individual preferences to elect a alternative. There are multiple voting methods (either absolute or relative judgments). For instance, we can consider reviewing a place in Google Maps as a voting mechanism because a u