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Rated, evaluative,[1] graded,[1] or cardinal voting systems are a class of voting methods which allow voters to state how strongly they support a candidate,[2] which involves giving each one a grade on a separate scale.[1] Cardinal methods (based on cardinal utility) and ordinal methods (based on ordinal utility) are the two categories of modern voting systems.[2][3]
The distribution of ratings for each candidate—i.e. the percentage of voters who assign them a particular score—is called their merit profile.[4] For example, if candidates are graded on a 4-point scale, one candidate's merit profile may be 25% on every possible rating (1, 2, 3, and 4), while a perfect candidate would have a merit profile where 100% of voters assign them a score of 4.
A key feature of evaluative voting is a form of independence: the voter can evaluate all the candidates in turn ... another feature of evaluative voting ... is that voters can express some degree of preference.
Ordinal utility is a measure of preferences in terms of rank orders—that is, first, second, etc. ... Cardinal utility is a measure of preferences on a scale of cardinal numbers, such as the scale from zero to one or the scale from one to ten.