The economics of database searching

August 11, 2011

(PhysOrg.com) -- Searching the internet might seem simple, but applying a little bit of economic theory to information retrieval can shed some light on the best search strategies to adopt, according to researchers.

Dr. Leif Azzopardi from the School of at the University of Glasgow took production theory from microeconomics and applied it to the process of searching the internet, or any other .

In economics, production theory deals with the process of turning inputs, like capital and labour, into outputs, like goods and services. Production theory helps to determine how resources can be efficiently turned into such products i.e. least effort, most gain.

Working on the premise that searching for information requires effort, such as assessing documents, and submitting queries, Dr. Azzopardi sought to consider what search strategies a user should employ to efficiently undertake a search when looking for a number of relevant documents.

Dr. Azzopardi said: “Short queries can be quite effective for finding one highly-relevant document, but searching for a number of relevant documents often requires numerous queries to be posed. Generally speaking, a user will only examine the first page or so of the result list.”

Dr. Azzopardi said: “We also know that longer queries are more effective, and that there is often more relevant items on subsequent pages. So are people being lazy when they search or are they being strategic and rational when they search?”

“Being able to answer such questions is important for interactive information retrieval because while behavioural and observational studies have been conducted, there is a lack of formal theory to explain why such observations are witnessed.”

Dr. Azzopardi conducted a simulated analysis that varied the way in which a simulated user interacted with three different types of database search methods: BM25, Boolean and TFIDF.

Boolean searches use logical connections to search terms – using AND, OR, NOT; and are typically used in patent or library search systems.

BM25 ranks documents based on relevance using the incidence of key words searched that are contained in the document; and TFIDF (term frequency-inverse document frequency) is another method of searching for relevant keywords within a document.

By applying production theory from economics Dr. Azzopardi was able to identify which search strategies users of different retrieval systems should use.

Overall, he found that BM25 systems supported a greater variety of search strategies than Boolean or TFIDF.  However, the most ‘cost-efficient’ search on a BM25 system involved examining only the first page or so of results and then posting further queries until the desired level of gain was achieved. This finding is consistent with how users search the internet using commercial search engines.

On the other hand using Boolean systems suggests users would have to delve deeper into the result listings looking at 100s of documents per query and issuing substantially more queries to achieve the same level of gain. However, this finding is consistent with how patent searchers interact with Boolean based patent systems.

Dr. Azzopardi said:  “This work provides the foundations on which to build formal methods for describing, understanding and explaining the interactions between a user and system.”

“It also shows that we can apply economics to human computer interaction, more generally, and therefore we can predict how a user will utilize a system.”

Explore further: Web searching made more successful with automated, personalized assistance system

More information: The research was presented at a conference of the Special Interest Group on Information Retrieval in Beijing in July and is published on the website of the Association for Computer Machinery. ( portal.acm.org/citation.cfm?id=2009923 )

Related Stories

Branding matters -- even when searching

June 28, 2007

Web searchers who evaluated identical search-engine results overwhelmingly favored Yahoo! and Google, providing evidence that branding matters as much on the Internet as off, according to a Penn State study.

If at first you don't succeed, let the search engine try

June 5, 2009

No matter how good a search engine is, it is sometimes necessary to change the search terms to get the information you need. But what if you did not have to change the search terms yourself? What if the search engine could ...

The engines of change

November 5, 2010

In today's wired world, search engines have changed the way people find data, and social searches are making it even easier to find exactly what you're looking for, with a little help from your friends. For example, a recent ...

Recommended for you

Not another new phone! But Nextbit's Robin is smarter

September 2, 2015

San Francisco-based Nextbit wants you to meet Robin, which they consider as the smarter smartphone. Their premise is that no one is making a smart smartphone; when you get so big it's hard to see the forest through the trees. ...

Team develops targeted drug delivery to lung

September 2, 2015

Researchers from Columbia Engineering and Columbia University Medical Center (CUMC) have developed a new method that can target delivery of very small volumes of drugs into the lung. Their approach, in which micro-liters ...

Team creates functional ultrathin solar cells

August 27, 2015

(Phys.org)—A team of researchers with Johannes Kepler University Linz in Austria has developed an ultrathin solar cell for use in lightweight and flexible applications. In their paper published in the journal Nature Materials, ...

Magnetic fields provide a new way to communicate wirelessly

September 1, 2015

Electrical engineers at the University of California, San Diego demonstrated a new wireless communication technique that works by sending magnetic signals through the human body. The new technology could offer a lower power ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.