Building Web Reputation Systems

Chapter 1. Reputation Systems Are Everywhere

Reputation systems impact your life every day, even when you don’t realize it. You need reputation to get through life efficiently, because reputation helps you make sound judgments in the absence of any better information. Reputation is even more important on the Web, which has trillions of pages to sort through—each one competing for your attention. Without reputation systems for things like search rankings, ratings and reviews, and spam filters, the Web would have become unusable years ago.

This book will clarify the concepts and terminology of reputation systems and define their mechanisms. With these tools, you can analyze existing models, or even design, deploy, and operate your own online reputation systems.

But, before all that, let us start at the beginning….

An Opinionated Conversation

Imagine the following conversation—maybe you’ve had one like it yourself. Robert is out to dinner with a client, Bill, and proudly shares some personal news.

He says, “My daughter Wendy is going to Harvard in the fall.”

“Really! I’m curious—how did you pick Harvard?” asks Bill.

“Why, it has the best reputation. Especially for law, and Wendy wants to be a lawyer.”

“Did she consider Yale? My boss is a Yale man—swears by the law school.”

“Heh. Yes, depending on who you ask, their programs are quite competitive. In the end, we really liked Harvard’s proximity. We won’t be more than an hour away.”

“Won’t it be expensive?”

“It’s certainly not cheap…but it is