Memex: A Browsing Assistant forCollaborative Archiving and

Mining of Surf Trails

Soumen ChakrabartiSandeep Srivastava

Mallela SubramanyamMitul Tiwari

Indian Institute of Technology Bombay

IITB 2000

Sources of Web information Sources already exploited

• Text on pages (keyword search)• Link between pages (popularity rating)• Topic taxonomies (query expansion)

Sources not exploited enough yet• Public surfing history• Public bookmarks

Collaboration is central to hypertext Lack of trust limits collaboration on Web

IITB 2000

Our goals Infrastructure to support spontaneous

formation of topic-based collaborative Web communities• Browsing assistant client• Community server

Mining algorithms for personal and community level topic management and collaborative resource discovery

Extensible API for plugging in additional hypertext analysis tools

IITB 2000

1: Create aMemex account(password sent

by email)

3: Allow the Memexclient to attach toyour Web browser

4: Log on to theMemex server

2: Install theMemex applet signing

certificate and visitthe applet page

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Memex clientapplet attachesto browser

Privacy choice

Function ta

bs

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Preparing toimport initialbookmarks

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Bookmarksimported

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For Memex to suggestan initial topic organization,select all bookmarks…

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…and send themto the clustering tab

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Switch to theclustering tab

URLs to beclusteredappear here

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Submit the URLsto the server-sideMemex clusteringdemon

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Check later if theserver has completedthe clustering task

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Two top-levelclusters aboutsoftware andmusic

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Expanding thesoftware clusterto study it inmore detail

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User can freelyreorganize URLplacement usingcut-and-paste

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User can freelyreorganize URLplacement usingcut-and-paste

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User can freelyreorganize URLplacement usingcut-and-paste

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Moving an entirefolder from thecluster tab…

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…to the foldertab together withexample URLs

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…to the foldertab together withexample URLs

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Folder names can beedited as per taste; thisalso gives Memexadditional clues aboutthe folder’s contents

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New folders can becreated to hold clustersfound in the cluster tab

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New folders can becreated to hold clustersfound in the cluster tab

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A topic hierarchy which istoo detailed for the user canbe flattened

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A topic hierarchy which istoo detailed for the user canbe flattened

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Groups of closely relatedURLs can be moved backto folders in the folder tab

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Groups of closely relatedURLs can be moved backto folders in the folder tab

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Memex helps the user derivea starting topic hierarchy fromunstructured bookmarks

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The user then continuesbrowsing in multiple sessions.Relevant pages found by othermembers of the communityand made public are availablefor collaborative surfing

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If permission is granted, theMemex applet monitors the trailthat the surfer follows anduploads it to the server forfurther analysis and mining

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If permission is granted, theMemex applet monitors the trailthat the surfer follows anduploads it to the server forfurther analysis and mining

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Such surf trails together withpage contents are valuableinputs to the Memex server-sidehypertext mining and resourcediscovery demons

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In the background, the Memexclassifier finds the most suitablefolders to assign to each historyitems. History is never deleted (diskis cheap). When the user refreshesthe view, surf history from othersand herself are found categorizedinto the user’s familiar topic tree.

‘?’ indicates that Memex is not

sure about the folder assignment.

Users can easily correct mistakes

and this forms additional

valuable training data.

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Automatic collaborativeclassification also lets usersreturn to a topic-restrictedsurfing context quickly, andreplay the last few surfingactions within that topicof interest.

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Personalized topic-basedhistory management is farsuperior to the one-dimensional history listprovided by popularbrowsers

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Users can switch topics witha single click, and browsingis not limited by the linear“back and forward” paradigmsupported by browsers.

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Users can switch topics witha single click, and browsingis not limited by the linear“back and forward” paradigmsupported by browsers.

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A flexible interactive searchlets the user locate any pageever visited from anywhereusing this account, combiningcontent with popularity, siteselections and timeliness

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A flexible interactive searchlets the user locate any pageever visited from anywhereusing this account, combiningcontent with popularity, siteselections and timeliness

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Close integration of theMemex client with thebrowser is non-trivial toimplement but adds greatlyto comfort and ease of use

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Memex system diagram

Browser

Memex server

Client JARVisit

Runningclient applet

Download

Attach

Eve

nt-

han

dle

r se

rvle

ts

Search

Folder

Context

Archive

Memex client-serverprotocol and workloadsharing negotiations

Relationalmetadata

Textindex

Min

ing

de

mo

ns

Topicmodels

Taxonomy synthesis

Resource discovery

Recommendation

Classification

Clustering

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Document workflow

Demon Registry

X

Per-document version queue

NODEtable

Crawler

Searchindexer

Classifierservice

Clusteringservice

Garbagecollector

Push newversion

Pop anddiscard

old version

BrowserMemexclient

Page visit andbookmarkingevents logged

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Autonomous topic organization Bookmarks often collected into topics Surfers use personal topic organization One-size-fits all taxonomy inadequate

• Many topics over-developed for most of us• http://dmoz.org/Sports/Hockey/Underwater_Hockey/

• But deeper interests often underdeveloped• Structure reorganization also desirable

Best taxonomy depends on community behavior as well as page content

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Autonomy and collaboration Personalization picking Yahoo nodes Complex relations between topics Need “simplest common ground”

• Coalesce similar topics where possible…• …without sacrificing individual taste

Sports

Hiking

Subsumption

User2User1Yahoo

Biz

Shops

Bikeshops

Sports

Cycling

Cycling

Bikeshops

Sports

User3

Tree ‘inversion’

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Taxonomy synthesis example

Generating themes makes map simpler But distorts contents of original folders Joint optimization gives best themes

Entertainment

Studios

Broadcasting

Media kpfa.org

bbc.co.uk

kron.com

channel4.com

kcbs.com

foxmovies.com

miramax.com

lucasfilms.com

Share document

Share folder

Share termsThemes

‘Radio’

‘Television’

‘Movies’

IITB 2000

Summary and project status Collaborative resource discovery and topic

management system Testbed for hypertext mining research Signed Java2 client

• Netscape 4.5+ available• IE5+ planned

Server for Unix and Windows• IBM UDB, Berkeley DB, servlets• Non-trivial to install and manage• Simple-to-use RPMs being planned

http://www.cse.iitb.ernet.in/~soumen