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Trust and Propaganda!
in Cyberspace!
Panagiotis Takis Metaxas
Computer Science Department
Wellesley College
Have you used the Web…!
to get informed?
to help you make decisions?
Financial
Medical
Political
Religious
Other?…
on your computer?
Your cell phone?
Your PDA?
Your thermostat?
Your toaster?
The Web is huge
> 50 billion (! ?)
static pages publicly available,
…growing every day
Much larger ,
if you count the “ deep web ”
Infinite ,
if you count pages created
on-the-fly
The Web is omnipresent
… but it can be unreliable!
Anyone can be an author on the web!
Email Spam anyone?!
50% of emails received at Wellesley College are spam!
… you like it or not!!
But Google is usually so good in finding info…
Why does it do that?
Why?! How do they do it? Web Spam:
Attempt to modify the web (its structure and contents),
and thus influence search engine results
in ways beneficial to web spammers
The Web is a Graph!
Directed Graph of Nodes and Arcs (directed edges)
Nodes = web pages
Arcs = hyperlinks from a page to another
A graph can be explored
A graph can be indexed
Access method Server and domain
URL
Path Document
http://www.wellesley.edu/CS/pmetaxas/index.html
crawl the
web
create
inverted index
Inverted index Search engine servers Document IDs How Google (and the other search engines) Work! user query THE WEB
Rank
results
1st Generation: How to Spam! “Keyword stuffing”: Add keywords, text, to increase content similarity Searching for Jennifer Aniston? SEX SEXY MONICA LEWINSKY JENNIFER LOPEZ CLAUDIA SCHIFFER CINDY CRAWFORD JENNIFER ANNISTON GILLIAN ANDERSON MADONNA NIKI TAYLOR ELLE MACPHERSON KATE MOSS CAROL ALT TYRA BANKS FREDERIQUE KATHY IRELAND PAM ANDERSON KAREN MULDER VALERIA MAZZA SHALOM HARLOW AMBER VALLETTA LAETITA CASTA BETTIE PAGE HEIDI KLUM PATRICIA FORD DAISY FUENTES KELLY BROOK SEX SEXY MONICA LEWINSKY JENNIFER LOPEZ CLAUDIA SCHIFFER CINDY CRAWFORD JENNIFER ANNISTON GILLIAN ANDERSON MADONNA NIKI TAYLOR ELLE MACPHERSON KATE MOSS CAROL ALT TYRA BANKS FREDERIQUE KATHY IRELAND PAM ANDERSON KAREN MULDER VALERIA MAZZA SHALOM HARLOW AMBER VALLETTA LAETITA CASTA BETTIE PAGE HEIDI KLUM PATRICIA FORD DAISY FUENTES KELLY BROOK SEX SEXY MONICA LEWINSKY JENNIFER LOPEZ CLAUDIA SCHIFFER CINDY CRAWFORD JENNIFER ANNISTON GILLIAN ANDERSON MADONNA NIKI TAYLOR ELLE MACPHERSON KATE MOSS CAROL ALT TYRA BANKS FREDERIQUE KATHY IRELAND PAM ANDERSON KAREN MULDER VALERIA MAZZA SHALOM HARLOW AMBER VALLETTA LAETITA CASTA BETTIE PAGE HEIDI KLUM PATRICIA FORD DAISY FUENTES KELLY BROOK SEX SEXY MONICA LEWINSKY JENNIFER LOPEZ CLAUDIA SCHIFFER CINDY CRAWFORD JENNIFER ANNISTON GILLIAN ANDERSON MADONNA NIKI TAYLOR ELLE MACPHERSON KATE MOSS CAROL ALT TYRA BANKS FREDERIQUE KATHY IRELAND PAM ANDERSON KAREN MULDER VALERIA MAZZA SHALOM HARLOW AMBER VALLETTA LAETITA CASTA BETTIE PAGE HEIDI KLUM PATRICIA FORD DAISY FUENTES KELLY BROOK 2nd Generation: Add Popularity! A hyperlink from a page in site A to some page in site B is considered a popularity vote from site A to site B Rank similar documents according to popularity How To Spam?
www.aa.com
www.bb.com
www.cc.com
1 www.dd.com
www.zz.com
2nd Generation: How to Spam! Create “Link Farms”: Heavily interconnected sites spam popularity 3rd Generation: Add Reputation! The reputation “PageRank” of a page Pi = the sum of a fraction of the reputations of all pages Pj that point to Pi Idea similar to academic co-citations Beautiful Math behind it
PR = principal eigenvector
of the web’s link matrix
PR equivalent to the chance
of randomly surfing to the page
How To Spam?
Unanswered Spam Attacks!
Business weapons
“more evil than satan”
Political weapon in pre-election season
“miserable failure”
“waffles”
“Clay Shaw” (+ 50 Republicans)
Misinformation
Promote hGH
Discredit AD/HD research
Activism / online protest
“Egypt”
“Jew”
Other uses we do not know?
“views expressed by the sites in your results are not in any way
endorsed by Google…”
Search Engines vs Web Spam!
Search Engine’s Action
1st Generation: Similarity
Content
2nd Generation: + Popularity
Content + Structure
3rd Generation: + Reputation
Content + Structure + Value
In the Works
Ranking based on
“the need behind the query”
Web Spammers Reaction
Add keywords so as
to increase content similarity
+ Create “ link farms ” of
heavily interconnected sites
+ Organize “ mutual admiration
societies ” of irrelevant
reputable sites
Is there a pattern on how to spam? Can you guess what they will do?
And Now For Something Completely(?) Different!
Propaganda:
Attempt to modify human behavior,
and thus influence people’s actions
in ways beneficial to propagandists
Theory of Propaganda
Developed by the Institute for Propaganda Analysis 1938-
Propagandistic Techniques (and ways of detecting propaganda)
Word games - associate good/bad concept with social entity
Glittering Generalities — Name Calling
Transfer - use special priviledges (e.g., office) to breach trust
Testimonial - famous non-experts’ claims
Plain Folk - people like us think this way
Bandwagon - everybody’s doing it, jump on the wagon
Card Stacking - use of bad logic
Societal Trust is (also) a Graph! Weighted Directed Graph of Nodes and Weighted Arcs
Nodes = Societal Entities (People, Ideas, …)
Arcs = Trust recommendation from an entity to another
Arc weight = Degree of entrustment
Then what is Propaganda?
Attempt to modify the Societal Trust Graph
in ways beneficial to propagandist
How to modify the Trust Graph?
Cognitive Hacking and Cyber Trust!
Pump & Dump stock schemes
The Emulex case
Word Games
Transfer
Gaining Access or Breaking into a computer system
for the purpose of modifying certain behaviors of a human user
in a way that violates the integrity of the overall system
Does not necessarily aim to fool a search engine
Famous examples:
How (not) To Solve The Problem!
Living in Cyberspace! Critical Thinking, Education
Realize how do we know what we know
“Of course it’s true; I saw it on the Internet!”
Cyber-social Structures that mimic Societal ones
Know why to trust or distrust
Who do you trust on a particular subject?
A Search Engine per Browser
Easier to fool one search engine than to fool millions of readers
Enable the reader to keep track of her trust network
Tools of cyber trust
How would you avoid the Emulex hoax?
Thank You!! PMetaxas@wellesley.edu
