One of the recurring topics at The Noisy Channel is exploratory search. Indeed, one of our readers recently took the initiative to upgrade the Wikipedia entry on exploratory search.
In the information retrieval literature. exploratory search comes across as a niche topic consigned to specialty workshops. A cursory reading of papers from the major information retrieval conferences would lead one to believe that most search problems boil down to improving relevance ranking, albeit with different techniques for different problems (e.g., expert search vs. document search) or domains (e.g., blogs vs. news).
But it’s not just the research community that has neglected exploratory search. When most non-academics think of search, they think of Google with its search box and ranked list of results. The interaction design of web search is anything but exploratory. To the extent that people engage in exploratory search on the web, they tend to do so in spite of, rather than because of, the tools at their disposal.
Should we conclude then that exploratory search is, in fact, a fringe use case?
According to Ryen White, Gary Marchionini, and Gheorghe Muresan:
Exploratory search can be used to describe an information-seeking problem context that is open-ended, persistent, and multi-faceted; and to describe information-seeking processes that are opportunistic, iterative, and multi-tactical. In the first sense, exploratory search is commonly used in scientific discovery, learning, and decision making contexts. In the second sense, exploratory tactics are used in all manner of information seeking and reflect seeker preferences and experience as much as the goal (Marchionini, 2006).
If we accept this dichotomy, then the first sense of exploratory search is a niche use case, while the second sense characterizes almost everything we call search. Perhaps it is more useful to ask what is not exploratory search.
Let me offer the following characterization of non-exploratory search:
- You know exactly what you want.
- You know exactly how to ask for it.
- You expect a search query to yield one of two responses:
- Success: you are presented with the object of your search.
- Failure: you learn that the object of your search is unavailable.
If any of these assumptions fails to hold, then the search problem is, to some extent, exploratory.
There are real non-exploratory search needs, such as navigational queries on the web and title searches in digital libraries. But these are, for most purposes, solved problems. Most of the open problems in information retrieval, at least in my view, apply to exploratory search scenarios. It would be nice to see more solutions that explicitly support the process of exploration.