computational social media lecture 02: friending -...
TRANSCRIPT
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computational social media
lecture 02: friendingpart 1
daniel gatica-perez
04.03.2015
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this lecture
introduction & definitions
a human-centric review of research on facebookdescriptive analysis of usersnetwork propertiesuser motivationsuser identitysocial interaction among usersthe real-name web: privacy & information disclosure
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Announcements
homework #1
paper reading session #1 each paper has a presenter and a discussant each session has a scribe let me know by tonight if you want to: present / discuss / scribe first come first served presentation slides + discussion notes will be put online
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facebook basic statistics (as of Dec 31, 2015)http://newsroom.fb.com/company-info/, accessed Feb 2016
Statistics 2013 2014 2015
monthly active users 1.23 B 1.39 B 1.59 B
mobile monthly active users 945 M 1.19 B 1.44 B
daily active users on average 757 M 890 M 1.04 B
daily active users outside U.S. & Canada 81% 82.4% 83.6%
employees 6337 9199 12691
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facebook 2013 year-in-review worldwide trendshttp://newsroom.fb.com/Trends/770/2013-Year-in-Review
Top Life EventsLife events people added to theirTimeline most frequently in 2013
1. Added a relationship, got engagedor got married2. Traveled3. Moved4. Ended a relationship5. First met a friend6. Added a family member, expectinga baby or had a baby7. Got a pet8. Lost a loved one9. Got a piercing10. Quit a habit
Most Talked About TopicsMost mentioned people andevents of 2013 around the world
1. Pope Francis2. Election3. Royal Baby4. Typhoon5. Margaret Thatcher6. Harlem Shake7. Miley Cyrus8. Boston Marathon9. Tour de France10. Nelson Mandela
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http://yearinreview.fb.com/2015/
Topics of the Year (World)
1. US presidential election2. Nov. 13 Attacks in Paris3. Syrian Civil War and Refugees4. Nepal Earthquakes5. Greek Debt Crisis6. Marriage Equality7. Fight Against ISIS8. Charlie Hebdo Attack9. Baltimore Protests10. Charleston Shooting
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definitions:social network site
“web-based [and mobile] services that allow individuals to
(1) construct a public or semi-public profile within a bounded system
(2) articulate a list of other users with whom they shared a connection
(3) view and traverse their list of connections and those made by otherswithin the system
the nature of these connections may vary from site to site.”
d. boyd and N. B. Ellison, “Social Network Sites: Definition, History and Scholarship,”Journal of Computer-Mediated Communication, 2007.
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understanding research on facebook(Wilson et al, 2012)
“..the questions,methods, andperspectiveswere so diverseand fragmentedthat it would beimpossible towrite a coherentsummary of theliterature.”
“…but we alsorealized thatwithoutsummarizing thecurrent trends thesituation wasunlikely toimprove.”412 articles
(end 2011)
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why study facebook?(and social media in general)
“new opportunities to study human behaviorthat previously had to rely in behaviors difficultto assess (like making friends and chatting)”
“measurable behavioral traces with levels ofecological validity that are hard to match inmost common research settings”
“the popularity of Facebook makes it a topicworthy of study in its own right”
“in addition to reflecting existing socialprocesses, they are spawning new ones bychanging the way people relate to one another”
“the rise of Facebook brings both newbenefits and dangers to society”
R. E. Wilson, S. D. Gosling, and L. T. Graham, A Review of Facebook Research in the Social Sciences,Perspectives on Psychological Science, 7(3), 203-220, 2012.
DeGolyer Library, Southern Methodist University @ flickr (cc)https://www.flickr.com/photos/41131493@N06/6863317608/
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research areas on facebook
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facebook users & articles:growth over time
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how to do research about facebook?
1. work or intern at facebook
2. recruit participants offline
3. recruit people via apps
4. crawl data
facebook data science teamhttps://www.facebook.com/data
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reading list #1: to be presented next week(11.03.2016)
M. Burke, L. Adamic, K. MarciniakFamilies on FacebookProc. AAAI Conf. on Weblogs and Social Media (ICWSM), 2013http://www.thoughtcrumbs.com/publications/burke_icwsm_2013_families_on_facebook.pdf
M. Kosinski, D. Stillwell, T. GraepelPrivate traits and attributes are predictable from digital records of human behaviorPNAS, 2013http://www.pnas.org/content/early/2013/03/06/1218772110.full.pdf
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reading session logistics
role 1: presenter read paper & prepare slides: 15 minute presentation points: (1) what problem is addressed? (2) what are the
contributions? (3) what is the technical approach? (4) what arethe main findings?
role 2: discussant read paper & prepare questions to guide discussion examples: (1) how to improve / extend the work? (2) what
implications do the ideas have in social media work and society?(3) are there any controversial issues? (4) any limitations?
role 3: scribe take notes of the group discussion for each paper write up summary of discussion (one page per paper)
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topic 1:descriptive analysis of users
who uses facebook and what do they do?
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graphs as models of networks:quick basics
All materials of this section are taken from:D. Easley and J. Kleinberg. Networks, Crowds, and Markets: Reasoning about a Highly Connected World. CambridgeUniversity Press, 2010. Chapter 2, http://www.cs.cornell.edu/home/kleinber/networks-book/
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edge
node
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paths and cycles
Path: sequence of nodes where each consecutive pair is connected by an edge
Simple path: paths that contain no repeated nodes
Cycle: a path with at least three edges, in which the first and last nodes are thesame, but otherwise all nodes are distinct
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connectivity
Connected component: a subset of thenodes such that:(i) every node in the subset has a path to
every other;(ii) the subset is not part of some larger
set with the property that every nodecan reach every other.
(i) says that the component is indeed internally connected(ii) says that it really is a free-standing piece of the graph
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giant components
Giant component: connectedcomponent that contains asignificant fraction of all thenodes in large networks
When a network contains a giantcomponent, it almost alwayscontains only one
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path length and distance between nodes
Path length: number of edges inthe sequence that comprises it
Distance between two nodes: lengthof the shortest path between them
l(MIT, BBN, RAND, UCLA) = 3l(MIT, UTAH) = 1
d(LINC, SRI) = 3
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breadth-first search: a method to determine distances
It searches a graph from a startingnode, reaching the closest nodes first
It serves as a conceptualframework to organize a graph’sstructure, arranging the nodesbased on their distances from afixed starting point.
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small-world phenomenon
six degrees of separation+ any two people are separated by no more than
six intermediate connections+ the world looks “small” given these short paths+ proposed by Frigyes Karinthy in short story (1929)+ popularized by John Guare’s Six Degrees ofSeparation play (1990)
“I read somewhere that everybody on this planet isseparated by only six other people. Six degrees ofseparation between us and everyone elseon this planet.”
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Stanley Milgram’s small-world experiment (1960s)
+ 296 volunteers living in US midwest+ they sent a message to a person living inBoston suburbs+ volunteers could not send message directlyto target (unless personal contact)+ they sent message to a personal contactwho was likely to know the target+ 64 chains reached the target+ avg. # of intermediate persons = 5.2(distance: 6.2)
people navigate short paths with success, even if entire network is not visible
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the anatomy of facebook(Backstrom et al 2011)
L. Backstrom, Anatomy of Facebook, 21.11.2011http://www.facebook.com/notes/facebook-data-team/anatomy-of-facebook/10150388519243859
L. Backstrom, P. Boldi, M. Rosa, J. Ugander, S. Vigna, Four Degrees of Separation, in Proc. ACM Int'l Conf. on WebScience (WebSci), Jun. 2012, http://arxiv.org/abs/1111.4570J. Ugander, B. Karrer, L. Backstrom, C. Marlow, The Anatomy of the Facebook Social Graph, Nov. 2011,http://arxiv.org/abs/1111.4503
721 million facebook users69 billion friendshipslargest social network ever studied
research questions:1. how many friends do people have?2. how many degrees of separation between any two users?
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how many friends?(Backstrom et al 2011)
10% of people: less than 10 friends20% of people: less than 25 friends50% (the median): less than 100 friendsaverage friend count = 190
cumulative degree distribution: % of people with less than X friends
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4 degrees of separation (degrees = intermediaries)(Backstrom et al 2011)
99.6% of user pairs are connected by at most 5 degrees (6 edges)92% connected by 4 degrees (5 edges)
average distance (2011) = 4.74average distance (2008) = 5.28
within same country, connectivity is even higher84% of all connections are between users in the same country
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4 degrees of separation, revisited 2016https://research.facebook.com/blog/three-and-a-half-degrees-of-separation/
average distance (2016) = 4.57average distance (2011) = 4.74average distance (2008) = 5.28
recomputed on entire FB graph1.59 B users
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homophily in facebook(Backstrom et al 2011)
users’ friends are most likely to be of similar age
homophily“tendency of individuals to associate and bond with
similar others” (wikipedia)birds of a feather flock together
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small-world phenomenon in MS instant messenger(Leskovec et al 2008)
240 million activeuser accounts
average distance = 6.6
J. Leskovec, and E. Horvitz, Planetary-scale views on a large instant-messaging network, Proc. World Wide Web Conf.(WWW), 2008.
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studying populations in a changing facebook
population growsfeatures changecompany evolves
1. “the network structure, in which users are grouped in networks of friends,buffers the users from most changes to the overall facebook demographics”
2. “changes are largely additive, with drastic changes becoming less commonas the site matures”
3. “change is to be expected and measured, not interpreted as a fatal designflaw -> culture shifts with time”
what is stable?what findings are long-term?
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topic 2:motivations
why do people use facebook?
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top reasons why people use facebookdesire to keep in touch with friends(Ellison et al. 2006)(Lampe et al. 2006)
develop social capitalbenefits from relationships
(Ellison et al. 2007)(Burke et al. 2010)
engage in social groominggossip & small talk
(Tufekci, 2008)(Gosling, 2009)
reduce boredom &loneliness(Burke et al. 2010)(Lampe et al. 2010)
participateadd content & join groups
(Viswanath et al. 2009)
credit: sean macentee @ flickr (cc): http://www.flickr.com/photos/smemon/5684115572/
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social grooming and facebook
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social grooming
Robin Dunbar (1998)gossip, small talk, people-curiosityhuman equivalent of social grooming in primateslanguage allowed people to live in larger groups (~150)
“essential to forging bonds, affirming relationships, displaying bonds, learningabout hierarchies and alliances”
“a way to figure out where we all stand in relation to each other”
“means to improve one’s reputation and access to resources and solidarity”
credit: lawrence murray @ flickr (cc): http://www.flickr.com/photos/lawmurray/3065124869/
R. Dunbar, Grooming, Gossip, and the Evolution of Language, Harvard University Press, 1998Z. Tufekci, Grooming, Gossip, Facebook and Myspace: What Can We Learn About Social Networking Sites fromNon-Users. Information, Communication and Society. Vol. 11, No. 4, pp. 544-564, Jun. 2008
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social grooming in facebook:living in 21st century with stone age social minds
Sam Gosling (2009)
“we need to stay in touch with our groups but their size has outstripped ourcognitive ability to keep up with them”
“facebook provides a tech crutch to bridge this gap”
“interactions are not as inane as they appear…conversations are personalbut not private, they publicly signal associations with others”
credit: momo @ flickr (cc): http://www.flickr.com/photos/kudumomo/5476683654/
S. Gosling, The Ancient Psychological Roots of Facebook Behavior, HBR Blog Network, Mar. 2009
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social grooming on facebook(Tufecki, 2008)
credit: momo @ flickr (cc): http://www.flickr.com/photos/kudumomo/5476683654/
Z. Tufekci, Grooming, Gossip, Facebook and Myspace: What Can We Learn About Social Networking Sites fromNon-Users. Information, Communication and Society. Vol. 11, No. 4, pp. 544-564, Jun. 2008http://userpages.umbc.edu/~zeynep/papers/ZeynepSocialGroomingandFacebook.pdf
survey on university student population85% on social network sitesnon-users: had no FB profile
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social grooming(Tufecki, 2008)
social network users:- “driven by curiosity about past
friends & how they changed- cruising the site: from profile to
profile & message to message- leaving a message was
important, not message per se”
non-users:- “i don’t understand what you get
out of looking at others’ profiles- why are you bothering me? i
haven’t seen you in 7 years- why gossiping? you don’t even
know this person”
credit: dan taylor @ flickr (cc): http://www.flickr.com/photos/dantaylor/2044337954
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how many people can one be friends with?
Dunbar’s number:
“The figure of 150 seems to represent themaximum number of individuals with whomwe can have a genuinely socialrelationship, the kind of relationship thatgoes with knowing who they are and howthey relate to us”
“It’s the number of people you would notfeel embarrassed about joining uninvitedfor a drink if you happened to bump intothem in a bar”
R. Dunbar, "Neocortex size as a constraint on group size in primates". Journal of Human Evolution, 22 (6), 1992http://en.wikipedia.org/wiki/Dunbar%27s_numberD. Bennett, The Dunbar number, from the guru of social networks, Jan. 2013http://www.businessweek.com/articles/2013-01-10/the-dunbar-number-from-the-guru-of-social-networks
credit: Robin Dunbar
intimates -> close personal friends -> friends -> acquaintances -> strangers
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homework #1:can all those people on FB be your friends?
1. watch the talk by Robin Dunbar at ICWSM 2012http://videolectures.net/icwsm2012_dunbar_facebook/
2. write a half-page recount of your own FB friends:- how many FB friends do you have?- how many are
(1) intimate (e.g. partner, parents, best friend)(2) close personal friend(3) friend(4) acquaintance(5) stranger (people-you-don’t-really-know-but-somehow-got-there;
- what is your FB Dunbar’s number?
3. if you are not on Facebook, your homework will be to report and present thecollected stats in class
DEADLINE: Tuesday 15.03.2015
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social capital and facebook
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social capital
“the sum of the resources, actual or virtual, that accrue to an individual byvirtue of possessing a durable network of more or less institutionalizedrelationships of mutual acquaintance and recognition” (Bordieu et al. 1992)
N. B. Ellison, C. Steinfield, C. Lampe, The Benefits of Facebook ‘‘Friends:’’ Social Capital and College Students’Use of Online Social Network Sites. Journal of Computer-Mediated Communication, Vol. 12, 2007
+ “benefits accumulated through relationships
+ allows a person to draw on resources from his/her networks+ useful, non-redundant information+ personal relationships
+ linked to positive social outcomes+ psychological well-being+ better public health+ lower crime rates+ commitment to community+ capacity for collective action”
credit: aerust @ flickr (cc): http://www.flickr.com/photos/aerust/9615757642
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credit: http://www.flickr.com/photos/hanspoldoja/5001818922 (cc)
types of social capital(Putnam, 2000; Granovetter, 1973)
bridging social capitalweak ties: connections that can
provide information but notemotional support
M.S. Granovetter, “The Strength of Weak Ties, American Journal of Sociology”, Vol. 78, No. 6, May 1973R. D. Putnam, Bowling Alone, The Collapse and Revival of American Community, Simon and Schuster, 2000N. B. Ellison, C. Steinfield, C. Lampe, The Benefits of Facebook ‘‘Friends:’’ Social Capital and College Students’ Use ofOnline Social Network Sites. Journal of Computer-Mediated Communication, Vol. 12, 2007
strength of an interpersonal tie“a combination of the amount oftime, the emotional intensity, the
intimacy, and the reciprocalservices that characterize the tie”
bonding social capitalemotionally close relationships
that can provide access to scarceresources: family and close friends
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does the internet increase social capital?(Nie, 2001; Bargh, 2004; Wellman, 2001)
YES
- enables new connections with similarinterests and goals
- allows weak ties to form, giving riseto bridging social capital
- helps to keep and sustain dispersednetworks
- facilitates community interaction &involvement in collocated networks
N. B. Ellison, C. Steinfield, C. Lampe, The Benefits of Facebook ‘‘Friends:’’ Social Capital and College Students’Use of Online Social Network Sites. Journal of Computer-Mediated Communication, Vol. 12, 2007
NO
- reduce f2f time with others
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social capital and facebook(Ellison, 2007) N= 286 college students (MSU)
#friends
time
attitudes
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scales for bridging & bonding capital
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results:bridgingsocialcapital
linear regressionof bridging socialcapital scalefrom FB andother factors
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results:bondingsocialcapital
linear regressionof bonding socialcapital scalefrom FB andother factors
limitations:- only students of
one campus- only self-reports
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social capital in facebook: actual usage(Burke et al. 2010)
M. Burke, C. Marlow, and T. Lento, Social Network Activity and Social Well-Being, in Proc. ACM CHI, Atlanta, Apr. 2010
N= 1193 Facebook english-speaking users (20 countries)
credit: paul butler, duncan hall @ flickr (cc): http://www.flickr.com/photos/dullhunk/5261568726/
+ aggregated FB data for two months
+ similar surveys to (Ellison, 2007)
+ three dimensions+ engagement: general interaction with site+ directed communication: interactions between
target user and another friend+ consumption: degree of a user’s attention to the
broadcasts shared by friends
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features extracted from facebook activity logs:general engagement
mean std
period: two months
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features extracted from facebook activity logs:directed communication and content consumption
mean std
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linear regression results
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in summary…
FB network size is modestly associated with increasedbridging & bonding social capital and reduced loneliness
FB directed communication is modestly associated withincreased bonding social capital and reduced loneliness
FB consumption is modestly associated with reduced bridgingsocial capital and increased loneliness
credit: dani lurie @ flickr (cc): http://www.flickr.com/photos/slushpup/2283426363
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what to remember
facebook as a research subjectsociotechnical system: allows to study human behavior
descriptive analysis of usersfour degrees of separation (and shrinking)facebook is dynamic; it has to be studied as such
user motivationssocial groomingsocial capital
