System and methods for collaborative recommendations

A method of adding predefined item categories to a recommendation service that uses collaborative filtering to recommend items to users from a set of service categories, comprising:

• providing users an option to rate individual items, including items that do not fall within any service category;
• when a user rates an item that does not fall within any service category, recording the item and associated user rating in a repository without adding the item to the service;
• and
• when a quantity of rated items recorded within the repository for a non-service-category reaches a level that represents a desired degree of reliability for recommending items within that category, adding the non-service-category to the service.

In a computer-implemented collaborative recommendations service in which items are recommended to users from a database within a set of service categories, the set of service categories being a subset of the item categories of the database, a method of adding categories to the service, comprising:

• (a) prompting users to rate items that fall outside the set of service categories;
• (b) storing ratings data resulting from (a) without adding the rated items to the service;
• and
• (c) when a quantity of ratings data stored in (b) for a non-service-category of the database reaches a selected level that represents a desired degree of reliability for recommending items in the non-service-category, adding the non-service-category to the service.

A system that implements a recommendation service, comprising:

• a database of items that fall within a plurality of categories;
• a recommendation service component which recommends items to users from the database within a subset of the plurality of categories ("service categories") using a collaborative filtering method;
• and
• a service populating component which:
• provides users an option to rate items, including non-service-items and items in non-service-categories;
• when a user rates a non-service-item that falls within a service category, adds the non-service-item to the service;
• and
• when a user rates a non-service-item that does not fall within any service category, records the item and associated user rating without adding the item to the service, to thereby collect data for adding non-service-categories to the service as desired rated-items per category levels are reached.

A method for generating a ratings profile for use within a recommendation service that recommends items to users within multiple service categories, comprising:

• prompting the user to specify a preference level for each of a plurality of the service categories;
• using the preference levels specified by the user to generate a list of items that reflects the user's category preferences;
• and
• prompting the user to rate items from the list.