A comparison between voting and rating

% at K2LAB home page

By Jacob Palme, e-mail jpalme@dsv.su.se, at the research group for CMC (Computer Mediated Communication), which is a part of the K2Lab laboratory at the DSV university department. Last revision: 27 January 1997.

Here is an attempt to discuss the similarities and differences between voting and rating as it will most commonly be implemented in web applications.

Definition.By voting is meant the collection of opinion on a specific, defined issue for the purpose of collecting information or supporting a decision. Voting can be either decisive or advisory, but advisory voting will probably be more common. By rating is meant the collection of value ratings on a large number of web objects from many raters in order to subject filtering of information for many users.
Start preparation.A very important process: Preparation of the voting agenda. No such start process.
When can opinions be cast?After the agenda is ready, usually for a limited period. After the object to be rated has been submitted and as long as the object exists.
Who can cast opinions?Sometimes a defined group, sometimes anyone. (a) The provider of a document for one kind of rates,(b) Anyone except the submitter and his friends and relatives, for another kind of rate.
Can the same person cast opinion on the same issue more than once? Can be permitted or disallowed, if allowed, the new opinion replaces the old. Same as for voting.
Is the individual cast opinion shown to other people? Can be yes or no depending on the issue. No, it should be secret to allow freer rating.
How is the opinion cast?By filling in a specially composed web form based on the voting agenda. Should be very simple and standardized and available whenever a user sees an object.
When are the collected opinion counted? Either every time a new vote is cast, or at a designated time when the voting closes. Any time the ratings are needed for filtering, or in advance to make filtering faster.
Where is the opinion stored?In a special data base object collected to the forum in which the voting is performed. In a large, general-purpose data base, available to any filtering agent whenever needed.
Who counts the opinion?Probably a specially designated vote counting agent. Either within the data base, or by the filtering agent.
How is the collected opinion counted?One or more social choice algorithms. One or more filtering support algorithms.

As seen from the table above, there are both similarities and differences. However, the last three rows in the table above, where the opinion is stored, who counts it, and how it is counted, is very different. And this is differences which are very important for implementation, and which thus means that the implementation will probably be very different for voting and rating as defined above.