Collaborative Filtering

From Social Patterns

Example

Slashdot popularized the idea of harnessing the preferences of the site's readership to vote articles up or down and (in theory) bring the highest quality articles and comments to the surface while burying the worst.

What

People need help finding the best contributions to online commnunity.

When

Use when you've got a large base of contributors and a wide range of quality.

How

Enable authenticated users to vote up or down, or otherwise rate content. Optionally give users with higher reputation status more privileges to highlight or hide content. Aggregrate the votes and use to determine sorting and display order.

At Slashdot, only comments above a rating threshold are displayed automatically in the thread. A reader can still expand a hidden comment to read it, or change their preferences to move the threshold.