Tuesday, June 24, 2008

What is (not) Exploratory Search?

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.

4 comments:

Pavel Serdyukov said...

If users know what and how to search something, then it more looks like a database system, doesn't it? Users know that it is indexed and know the key. It is hardly exploratory, of course. It is interesting to divide exploratory search also into three kinds: one helps to "explore" personal memory (re-find things, recall names for things), second helps to explore how to name a known thing to find it (navigational), and third helps to really discover the world - find things with desired features, or change desires.

Daniel Tunkelang said...

Pavel, I like that breakdown of exploration, and it addresses my frustration with people who consider "known item" search as the antitheses of exploratory search.

As for non-exploratory search looking like a database system, my only counter-reaction is that I think of databases primarily as relational databases. In a relational database, the biggest challenge is understanding the schema well enough to construct the right queries. But I'd agree with you in the context of a denormalized database.

Max L. Wilson said...

daniel, you might be interested to read what CWI (Amsterdam) put into JCDL08: http://doi.acm.org/10.1145/1378889.1378897.

The report, really, showed that in the environment of museum curators, quick lookups were the minority case. they had an interesting breakdown of seeking types, but i think it was 63% that were information gathering tasks.

have an excellent workshop!

Daniel Tunkelang said...

Max, thanks for the link! A colleague at Endeca also pointed me back to the 2002 CACM paper by Marti Hearst et al., Finding the flow in web site search.

Tuesday, June 24, 2008

What is (not) Exploratory Search?

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.

4 comments:

Pavel Serdyukov said...

If users know what and how to search something, then it more looks like a database system, doesn't it? Users know that it is indexed and know the key. It is hardly exploratory, of course. It is interesting to divide exploratory search also into three kinds: one helps to "explore" personal memory (re-find things, recall names for things), second helps to explore how to name a known thing to find it (navigational), and third helps to really discover the world - find things with desired features, or change desires.

Daniel Tunkelang said...

Pavel, I like that breakdown of exploration, and it addresses my frustration with people who consider "known item" search as the antitheses of exploratory search.

As for non-exploratory search looking like a database system, my only counter-reaction is that I think of databases primarily as relational databases. In a relational database, the biggest challenge is understanding the schema well enough to construct the right queries. But I'd agree with you in the context of a denormalized database.

Max L. Wilson said...

daniel, you might be interested to read what CWI (Amsterdam) put into JCDL08: http://doi.acm.org/10.1145/1378889.1378897.

The report, really, showed that in the environment of museum curators, quick lookups were the minority case. they had an interesting breakdown of seeking types, but i think it was 63% that were information gathering tasks.

have an excellent workshop!

Daniel Tunkelang said...

Max, thanks for the link! A colleague at Endeca also pointed me back to the 2002 CACM paper by Marti Hearst et al., Finding the flow in web site search.

Tuesday, June 24, 2008

What is (not) Exploratory Search?

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.

4 comments:

Pavel Serdyukov said...

If users know what and how to search something, then it more looks like a database system, doesn't it? Users know that it is indexed and know the key. It is hardly exploratory, of course. It is interesting to divide exploratory search also into three kinds: one helps to "explore" personal memory (re-find things, recall names for things), second helps to explore how to name a known thing to find it (navigational), and third helps to really discover the world - find things with desired features, or change desires.

Daniel Tunkelang said...

Pavel, I like that breakdown of exploration, and it addresses my frustration with people who consider "known item" search as the antitheses of exploratory search.

As for non-exploratory search looking like a database system, my only counter-reaction is that I think of databases primarily as relational databases. In a relational database, the biggest challenge is understanding the schema well enough to construct the right queries. But I'd agree with you in the context of a denormalized database.

Max L. Wilson said...

daniel, you might be interested to read what CWI (Amsterdam) put into JCDL08: http://doi.acm.org/10.1145/1378889.1378897.

The report, really, showed that in the environment of museum curators, quick lookups were the minority case. they had an interesting breakdown of seeking types, but i think it was 63% that were information gathering tasks.

have an excellent workshop!

Daniel Tunkelang said...

Max, thanks for the link! A colleague at Endeca also pointed me back to the 2002 CACM paper by Marti Hearst et al., Finding the flow in web site search.