Saturday, 28 June 2008

the best way to provide faceted search?

As research has produced an increasing number of insights into the different ways of providing faceted metadata to users in the form of a faceted browser, the question has become: what actually is the best way to provide faceted search? This same question has not really been seen in typical information retrieval, as each bit of research has (usually) incrementally improved the system performance, and a good keyword-based search system will try to include all the advancements in their UI (not that Google is providing interactive query refinements).

We actually do see faceted search all over the place. iTunes has it in their 'browser' function (3 columns that filter to the right). Google product search lets you refine by facets like brand and price (each facet filters every other facet). Endeca seem to be selling it to everyone these days (right on!), including Walmart and Borders.

There are actually 2 layers to this question: how best to provide a faceted classification and how best to provide a faceted browser. The earlier has been well investigated, with advice from Marti Hearst. Endeca certainly seem to ask 'after each click in a facet, what is the best set of facets and values to show the user?'. The second question is less well known. Even one of Endeca's clients, the NCSU library, are asking: should we have the facets on the left or the right?, should we place a breadcrumb or a list of decisions?. How does this affect the user?

Further to these layout questions, I have been trying to work out for a while now whether the structured and consistent iTunes approach is better or worse than the dynamic adaptive approach taken by Endeca? Especially with all the additional functionality (e.g. column swapping and backward highlighting) we have been adding to the iTunes-style approach with mSpace. There are even more additional questions to ask. maybe its a case of when is one better than the other? Finally, can we somehow take the best of both worlds, so that we can figure out what to add to our faceted browsers that make them incrementally strong.


Daniel Tunkelang said...

Max, you're right to note that Endeca focuses more on what information to communicate to users rather than on the user interface details. We do have folks who specialize in the latter and work with customers on UI best practices, but one of the strengths of our offering is the flexibility we offer our customers in how they design applications.

You might find Peter Morville's Search Patterns collection interesting, e.g., this set on faceted navigation.

Max L. Wilson said...

wow interesting link daniel, thank you.

I'm totally sure you've got a strong UI team for designing the front end! I didnt mean to suggest otherwise. The best-facets-for-decision policy, though, is my favourite thing about Endeca sites.