What is Epinions.com? What is your role? Also, what is the "Web of Trust", and how does it operate? 

Epinions.com is an attempt to create a marketplace for content that is based on a scalable model for many-to-many communications. What do I mean by that? 

Marketplace for Content: The goal is to make it very easy to earn money off one's creative efforts, however small they may be. Almost everyone is an expert in something, but given the high barrier to monetizing that expertise, most of that expertise is never fully made available to those who might want it. 

So, for example, Jane Doe might know a lot about baby strollers, but it is unlikely that she is going to find the time and energy to either join the staff of a magazine or even become a freelance writer. As a result, the only people who benefit from her expertise are her friends. The hope is that if she can earn some potentially serious money by writing about strollers on epinions.com, more people are likely to benefit from her knowledge. 

Scalable many-to-many communications.  Usenet is still the only real many-to-many communication medium. Usenet however has scaled very poorly with volume and noise. 

In many-to-many communication, who is saying something is at least as important as what is being said. 

In the real world, we use "word of mouth " as a filter/attractor for information. Word of mouth recommendations provide "branding" for individuals. When one sees a thousand varieties of a product and don't know which one to choose, one is likely to choose a brand that is recommended to them. Similarly, when you are looking for advice on a topic, you doesn't rush out to the street and ask the first five people for advice. You ask people you know and trust or people they recommend for advice. We call this your "Web Of Trust". 

The epinions.com site is trying to provide an online version of this important real-world phenomenon. Any information we present to you is potentially reshaped by your Web of Trust. Everything from the search results to product recommendations is generated and modulated by the web of trust. 

Real world phenomenon are limited by the spatio-temporal constraints of the real world. You have to catch your friend on the phone, it takes him/her time, you don't know all your friend's friends, etc. At least some of these constraints can be removed from the online version of the Web Of Trust. So, for example, the system can easily calculate everyone trusted by those you trust and percolate up reviews from them and reviews they have rated highly. This corresponds in the real world to keeping complete track of all your friend's friends --- something that is pretty impossible to do. 

We have many many thousands of trust statements in the system. Based on anecdotal evidence, those who have started using it end up completely depending on it to navigate the site. 

The next step is to introduce other related real world entities such as groups --- everything from high school peer groups to organizations such as the Sierra Club. Ratings and value judgments by these groups deeply affect what information we consume. The online version of groups should be interesting!

My contributions to epinions have been all over the place. I created the incentive system and web of trust. I also architected our back end and wrote a substantial amount of the code. I did the first version of our taxonomy. Until recently, I also managed our engineering team. But now that we have a real manager, I will probably just focus on product development. 

What steps did you take to ensure that the epinions web site was easy to use, easy to learn, and generally effective for users? For example, what kind of usability and quality testing did you perform?

This work is on-going and I expect us to continually make lots of small improvements. Any suggestions? 

[Editor's note: I have a few ideas, but I'd like to ask WebWord.com readers for feedback. If you have ideas, please email me. I'll collect your responses and forward them. Perhaps I'll write a brief report too. Let me know what you think!]

How does the epinions incentive systems work? How does the incentive system influence the quality and usability of the reviews? 

The incentive system is very simple. You get paid for every page view for every review. In order to reduce exposure to gaming, we only count the number of page views from registered users (but make up for the reduced page views by increasing the amount paid out per page view). 

One of the important decisions we took was to pay the incentive independent of whether a reader ended up buying something or not. So, a frank review that recommends against buying something will be incentiviced at the same rate as one which urges the reader to buy it. 

What makes a review great? Similarly, what factors drive the ratings of reviews? 

This depends completely on the topic and the context of the reader. Imagine epinions on a topic where folks could really use something like the web of trust --- health. The usefulness of a piece of information about some ailment like whooping cough is largely a function of why you are reading it, your background, etc. 

All else being equal, I am partial to longer reviews. 

Tell us something really amazing or revealing about epinions. Or, tell us something that is exclusive to this interview. Be creative. 

I think I already have. Epinions is not just about product reviews. Its much more ambitious --- its a platform for content distribution. 

Final comments? Shameless plugs? Words of wisdom? Words of wisdom? 

Are you seditious or something, asking an engineer for words of wisdom? 

Thanks Guha!

[ Editor's note: Interested in writing your own reviews? Want to earn money? Join Now! ]

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