Building Web Reputation Systems

Preface

What Is This Book About?

Today’s Web is the product of over a billion hands and minds. Around the clock and around the globe, people are pumping out contributions small and large: full-length features on Vimeo, video shorts on YouTube, comments on Blogger, discussions on Yahoo! Groups, and tagged-and-titled Del.icio.us bookmarks. User-generated content and robust crowd participation have become the hallmarks of Web 2.0.

But the booming popularity of social media has brought with it a whole new set of challenges for those who create websites and online communities, as well as for the users who consume those sites:

• Problems of scale (how to manage—and present—an overwhelming inflow of user contributions)

• Problems of quality (how to tell the good stuff from the bad)

• Problems of engagement (how to reward contributors in a way that keeps them coming back)

• Problems of moderation (how to “stamp out” the worst stuff quickly and efficiently)

Reputation systems can provide an effective solution to all of these problems.

Reputation and Karma: Two Simple Definitions

Reputation

Information used to make a value judgment about an object or person

Karma

The reputation(s) for a user

What is reputation in an online community? In its broadest sense, reputation is information used to make a value judgment about an object or a person. There are potentially many components to reputation. For example, karma is a reputation score for a user in a community, and it may be an aggregation of answers to the following: ...