Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Buzzwords of history, revealed by computer scans, indicate new ways of searching the Web

19.02.2003


In the years after the American Revolution, U.S. presidents were talking about the British a lot, and then about militias, France and Spain. In the mid-19th century, words like "emancipation," "slaves" and "rebellion" popped up in their speeches. In the early 20th century, presidents started using a lot of business-expansion words, soon to be replaced by "depression."



A couple of decades later they spoke of atoms and communism. By the 1990s, buzzwords prevailed.

Jon Kleinberg, a professor of computer science at Cornell University, Ithaca, N.Y., has developed a method for a computer to find the topics that dominate a discussion at a particular time by scanning large collections of documents for sudden, rapid bursts of words. Among other tests of the method, he scanned presidential State of the Union addresses from 1790 to the present and created a list of words that eerily reflects historical trends. The technique, he suggests, could have many "data mining" applications, including searching the Web or studying trends in society as reflected in Web pages.


Kleinberg will emphasize the Web applications of his searching technique in a talk, "Web Structure and the Design of Search Algorithms," at the annual meeting of the American Association for the Advancement of Science (AAAS) in Denver on Feb. 18. He is taking part in a symposium on "Modeling the Internet and the World Wide Web"

Kleinberg says he got the idea of searching over time while trying to deal with his own flood of incoming e-mail. He reasoned that when an important topic comes up for discussion, keywords related to the topic will show a sudden increase in frequency. A search for these words that suddenly appear more often might, he theorized, provide ways to categorize messages.


He devised a search algorithm that looks for "burstiness," measuring not just the number of times words appear, but the rate of increase in those numbers over time. Programs based on his algorithm can scan text that varies with time and flag the most "bursty" words. "The method is motivated by probability models used to analyze the behavior of communication networks, where burstiness occurs in the traffic due to congestion and hot spots," he explains.

In his own e-mail -- largely from other computer scientists -- he quickly found keywords relating to hot topics. In mail from students he found bursts in the word "prelim" shortly before each midterm exam. Later, he tried the same technique on the texts of State of the Union addresses, all of which are available on the Web, from Washington in 1790 through George W. Bush in 2002. From these speeches he produced a long list of words (see attached table) that summarizes American politics from early revolutionary fervor up to the age of the modern speechwriter.

While we already know about these trends in American history, Kleinberg points out, a computer doesn’t, and it has found these ideas just by scanning raw text. So such a technique should work just as well on historical records in obscure situations where we have no idea what the important terms or keywords are. It might even be used to screen e-mail "chatter" by terrorists. Sociologists, Kleinberg adds, may find it interesting to look for trends in personal Web logs popularly known as "blogs."

For searching the Web, Kleinberg suggests, such a technique could help zero in on what a searcher wants by recognizing the time context of such material as news stories. For instance, he says, a person searching for the word "sniper" today is likely to be looking for information about the recent attacks around the nation’s capital -- but the same search nearly four decades ago might have come from someone interested in the Kennedy assassination.

In his AAAS talk Kleinberg also explores other Web-searching techniques. A few years ago, he suggested that a way to find the most useful Web sites on a particular subject would be to look at the way they are linked to one another. Sites that are "linked to" by many others are probably "authorities." Sites that link to many others are likely to be "hubs." The most authoritative sites on a topic would be the ones that are linked to most often by the most active hubs, he reasoned. A variation on this idea is used by Google, and a more formal version is being used in a new search engine called Teoma http://www.teoma.com .

Kleinberg and others have found that despite its anarchy, there is a great deal of "self-organization" on the Web. In a variation on the "six degrees of separation" idea, Kleinberg says, almost every site on the Web can be reached from almost any other through a series of steps. The structure seems to be a bit like the Milky Way galaxy, with a very dense "core" of heavily interconnected sites surrounded by less dense regions. Nodes outside the core are divided into three categories: "upstream" nodes that link to the core but cannot be reached from it; "downstream" nodes that can be reached from the core but don’t link back to it; and isolated "tendrils" that are not linked directly to the core at all.

Within this structure there are many "communities" of sites representing common interests that are extensively linked to one another. So, Kleinberg suggests, searches might be done by following along the link paths from one site to another, as well as just scanning an index of everything.

"Deeper analysis, exposing the structure of communities embedded in the Web, raises the prospect of bringing together individuals with common interests and lowering barriers to communication," Kleinberg concludes.

Bill Steele | Cornell News
Further information:
http://www.news.cornell.edu/releases/Feb03/AAAS.Kleinberg.bursty.ws.html
http://www.cs.cornell.edu/home/kleinber/
http://www.teoma.com

More articles from Information Technology:

nachricht Smarter robot vacuum cleaners for automated office cleaning
15.08.2017 | Fraunhofer-Institut für Arbeitswirtschaft und Organisation IAO

nachricht Researchers 3-D print first truly microfluidic 'lab on a chipl devices
15.08.2017 | Brigham Young University

All articles from Information Technology >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

Im Focus: Scientists improve forecast of increasing hazard on Ecuadorian volcano

Researchers from the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science, the Italian Space Agency (ASI), and the Instituto Geofisico--Escuela Politecnica Nacional (IGEPN) of Ecuador, showed an increasing volcanic danger on Cotopaxi in Ecuador using a powerful technique known as Interferometric Synthetic Aperture Radar (InSAR).

The Andes region in which Cotopaxi volcano is located is known to contain some of the world's most serious volcanic hazard. A mid- to large-size eruption has...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

New thruster design increases efficiency for future spaceflight

16.08.2017 | Physics and Astronomy

Transporting spin: A graphene and boron nitride heterostructure creates large spin signals

16.08.2017 | Materials Sciences

A new method for the 3-D printing of living tissues

16.08.2017 | Interdisciplinary Research

VideoLinks
B2B-VideoLinks
More VideoLinks >>>