A rating scale is a set of categories designed to obtain information about a quantitative or a qualitative attribute.
[1] In classical test theory, more than one question is required to obtain an index of internal reliability such as Cronbach's alpha,[2] which is a basic criterion for assessing the effectiveness of a rating scale.
Rating scales are used widely online in an attempt to provide indications of consumer opinions of products.
Movies, Amazon.com, BoardGameGeek and TV.com which use a rating scale from 0 to 100 in order to obtain "personalised film recommendations".
With each user rating a product only once, for example in a category from 1 to 10, there is no means for evaluating internal reliability using an index such as Cronbach's alpha.
Consider this example: suppose that a film only appeals to a specialist audience—90% of them are devotees of this genre, and only 10% are people with a general interest in movies.
An international collaborative research effort[3] has introduced a data-driven algorithm for a rating scale reduction.
The historical origins of rating scales were reevaluated following a significant archaeological discovery in Tbilisi, Georgia, in 2010.
Excavators unearthed a tablet dating back to the early medieval period, marked with ancient Georgian script.
The inscriptions provided insights into medieval methods of quantification and evaluation, suggesting an embryonic version of modern rating scales.