computational social media lecture 02: friending

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1 computational social media lecture 02: friending part 1 daniel gatica-perez this lecture and next one introduction & definitions a human-centric review of research on facebook descriptive analysis of users network properties user motivations user identity social interaction among users the real-name web: privacy & information disclosure 1

2 announcements homework #1: announced today binary grade: pass/failed due: tuesday paper reading session #1: announced today rank papers by interest, let me know by tonight first come first served each paper has a presenter and a discussant each session has a scribe presentation slides + discussion notes will go on webpage & blog facebook basic statistics (Dec ) accessed Mar 2015 Statistics monthly active users 1.23 B 1.39 B mobile monthly active users 945 M 1.19 B daily active users on average 757 M 890 M daily active users outside U.S. & Canada 81% 82.4% employees

3 facebook 2013 year-in-review worldwide trends Top Life Events Life events people added to their Timeline most frequently in Added a relationship, got engaged or got married 2. Traveled 3. Moved 4. Ended a relationship 5. First met a friend 6. Added a family member, expecting a baby or had a baby 7. Got a pet 8. Lost a loved one 9. Got a piercing 10. Quit a habit Most Talked About Topics Most mentioned people and events of 2013 around the world 1. Pope Francis 2. Election 3. Royal Baby 4. Typhoon 5. Margaret Thatcher 6. Harlem Shake 7. Miley Cyrus 8. Boston Marathon 9. Tour de France 10. Nelson Mandela Topics of the Year (World) 1. World Cup 2. Ebola 3. Brazil Elections 4. Robin Williams 5. Ice Bucket Challenge 6. Gaza Conflict 7. Malaysia Airlines 8. Super Bowl 9. Michael Brown / Ferguson 10. Sochi Winter Olympics 3

4 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 others within 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, differences between social network site vs. social networking site social networking : - emphasizes initiating relationships, often with strangers - dating sites social network sites: - enable users to articulate and make visible their extended social networks - meeting strangers is possible but not necessarily the primary practice - linkedin, facebook d. boyd and N. B. Ellison, Social Network Sites: Definition, History and Scholarship, Journal of Computer-Mediated Communication,

5 understanding research on facebook (Wilson et al, 2012)..the questions, methods, and perspectives were so diverse and fragmented that it would be impossible to write a coherent summary of the literature. 412 articles (end 2011) but we also realized that without summarizing the current trends the situation was unlikely to improve. why study facebook? (and social media in general) new opportunities to study human behavior that previously had to rely in behaviors difficult to assess (like making friends and chatting) measurable behavioral traces with levels of ecological validity that are hard to match in most common research settings the tremendous popularity of Facebook makes it a topic worthy of study in its own right in addition to reflecting existing social processes, they are spawning new ones by changing the way people relate to one another the rise of Facebook brings both new benefits 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), ,

6 research areas on facebook facebook users & articles: growth over time 6

7 how have people studied facebook? 1. work or intern at facebook 2. recruit participants offline 3. recruit people via apps 4. crawl data facebook data science team reading list #1 J. Chang, I. Rosenn, L. Backstrom, C. Marlow epluribus: ethnicity in social networks Proc. AAAI Conf. on Weblogs and Social Media (ICWSM), M. Burke, L. Adamic, K. Marciniak Families on Facebook Proc. AAAI Conf. on Weblogs and Social Media (ICWSM), book.pdf 7

8 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 are the main results / 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) topic 1: descriptive analysis of users who uses facebook and what do they do? 8

9 we live in the network hereby you give us the right to collect information about you you (in 2012, according to FB) had 130 friends shared 90 pieces of content a month connected to 80 community pages, groups & events 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. Cambridge University Press, Chapter 2, 9

10 node edge 10

11 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 the same, but otherwise all nodes are distinct connectivity Connected component: a subset of the nodes 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 node can 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 11

12 giant components Giant component: connected component that contains a significant fraction of all the nodes in large networks When a network contains a giant component, it almost always contains only one path length and distance between nodes Path length: number of edges in the sequence that comprises it Distance between two nodes: length of the shortest path between them l(mit, BBN, RAND, UCLA) = 3 l(mit, UTAH) = 1 d(linc, SRI) = 3 12

13 breadth-first search: a method to determine distances It searches a graph from a starting node, reaching the closest nodes first It serves as a conceptual framework to organize a graph s structure, arranging the nodes based on their distances from a fixed starting point. 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 of Separation play (1990) I read somewhere that everybody on this planet is separated by only six other people. Six degrees of separation between us and everyone else on this planet. 13

14 Stanley Milgram s small-world experiment (1960s) volunteers living in US midwest + they sent a message to a person living in Boston suburbs + volunteers could not send message directly to target (unless personal contact) + they sent message to a personal contact who was likely to know the target + 64 chains reached the target + avg. # of intermediate persons = 5.2 (~6 hops) people navigate short paths with success, even if entire network is not visible the anatomy of facebook (Backstrom et al 2011) 721 million facebook users 69 billion friendships largest social network ever studied research questions: 1. how many friends do people have? 2. how many degrees of separation between any two users? L. Backstrom, Anatomy of Facebook, L. Backstrom, P. Boldi, M. Rosa, J. Ugander, S. Vigna, Four Degrees of Separation, in Proc. ACM Int'l Conf. on Web Science (WebSci), Jun. 2012, J. Ugander, B. Karrer, L. Backstrom, C. Marlow, The Anatomy of the Facebook Social Graph, Nov. 2011, 14

15 how many friends? (Backstrom et al 2011) cumulative degree distribution: % of people with less than X friends 10% of people: less than 10 friends 20% of people: less than 25 friends 50% (the median): less than 100 friends average friend count = degrees of separation (Backstrom et al 2011) 99.6% of user pairs are connected by at most 5 degrees (6 hops) 92% connected by four degrees (5 hops) average distance (2011) = 4.74 hops average distance (2008) = 5.28 hops within same country, connectivity is even higher 84% of all connections are between users in the same country 15

16 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 small-world phenomenon in MS instant messenger (Leskovec et al 2008) 240 million active user 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),

17 demographics in facebook: ethnicity (Chang et al 2010) 77,000 American facebook profiles main goal: understand ethnic representation patterns in FB in the US population J. Chang, I. Rosenn, L. Backstrom,C. Marlow, epluribus: Ethnicity in Social Networks,, in Proc. AAAI Conf. on Weblogs and Social Media (ICWSM), 2010 open issues: cross-cultural studies based on actual behavior self-reports: fail to show how people vary across cultures as social norms can shape responses example: are Mexicans more sociable than Americans? Mexico vs. USA in daily life (not FB): - self-reports: Mexicans reported to be less sociable than Americans - mobile sensing: Mexicans behaved more socially in their daily life iear, App Store on itunes (credit: Matthias Mehl, U. Arizona) N. Ramirez-Esparza, M. Mehl, J. Alvarez-Bermudez, J. Pennebaker, Are Mexicans more or less sociable than Americans? Insights from a naturalistic observation study, Journal of Research in Personality, Vol. 43, pp. 1-7,

18 studying populations in a changing facebook population grows features change company evolves what is stable? what findings are long-term? 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 common as the site matures 3. change is to be expected and measured, not interpreted as a fatal design flaw -> culture shifts with time topic 2: motivations why do people use facebook? 18

19 top reasons why people use facebook desire to keep in touch with friends (Ellison et al. 2006) (Lampe et al. 2006) engage in social grooming gossip & small talk (Tufekci, 2008) (Gosling, 2009) develop social capital benefits from relationships (Ellison et al. 2007) (Burke et al. 2010) reduce boredom & loneliness (Burke et al. 2010) (Lampe et al. 2010) participate add content & join groups (Viswanath et al. 2009) credit: sean flickr (cc): social grooming and facebook 19

20 social grooming Robin Dunbar (1998) gossip, small talk, people-curiosity human equivalent of social grooming in primates language allowed people to live in larger groups (~150) essential to forging bonds, affirming relationships, displaying bonds, learning about 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 R. Dunbar, Grooming, Gossip, and the Evolution of Language, Harvard University Press, 1998 Z. Tufekci, Grooming, Gossip, Facebook and Myspace: What Can We Learn About Social Networking Sites from Non-Users. Information, Communication and Society. Vol. 11, No. 4, pp , Jun credit: lawrence flickr (cc): social grooming in facebook: living in 21 st century with stone age social minds Sam Gosling (2009) we need to stay in touch with our groups but their size has outstripped our cognitive 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 personal but not private, they publicly signal associations with others S. Gosling, The Ancient Psychological Roots of Facebook Behavior, HBR Blog Network, Mar credit: flickr (cc): 20

21 social grooming on facebook (Tufecki, 2008) survey on university student population 85% on social network sites no users: had no profile Z. Tufekci, Grooming, Gossip, Facebook and Myspace: What Can We Learn About Social Networking Sites from Non-Users. Information, Communication and Society. Vol. 11, No. 4, pp , Jun credit: flickr (cc): 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 flickr (cc): 21

22 how many people can one be friends with? Dunbar s number: The figure of 150 seems to represent the maximum number of individuals with whom we can have a genuinely social relationship, the kind of relationship that goes with knowing who they are and how they relate to us Putting it another way, it s the number of people you would not feel embarrassed about joining uninvited for a drink if you happened to bump into them in a bar credit: Robin Dunbar intimates -> close personal friends -> friends -> acquaintances -> strangers R. Dunbar, "Neocortex size as a constraint on group size in primates". Journal of Human Evolution, 22 (6), D. Bennett, The Dunbar number, from the guru of social networks, Jan homework #1: can all those people on FB be your friends? 1. watch the talk by Robin Dunbar at ICWSM write a half-page recount of your own FB friends: - how many FB friends do you have? - how many are family; partner; close current friends; past friends; current work colleagues; past work colleagues; acquaintances; professional contacts; people-you-don t-really know-butsomehow-got-there; - what is your FB Dunbar s number? 3. if you are not on Facebook, talk to me after class DEADLINE: Tuesday

23 social capital and facebook social capital the sum of the resources, actual or virtual, that accrue to an individual by virtue of possessing a durable network of more or less institutionalized relationships of mutual acquaintance and recognition (Bordieu et al. 1992) + 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 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 credit: flickr (cc): 23

24 types of social capital (Putnam, 2000; Granovetter, 1973) strength of an interpersonal tie a combination of the amount of time, the emotional intensity, the intimacy, and the reciprocal services that characterize the tie bridging social capital weak ties: connections that can provide information but not emotional support bonding social capital emotionally close relationships that can provide access to scarce resources: family and close friends M.S. Granovetter, The Strength of Weak Ties, American Journal of Sociology, Vol. 78, No. 6, May 1973 R. D. Putnam, Bowling Alone, The Collapse and Revival of American Community, Simon and Schuster, 2000 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 credit: (cc) does the internet increase social capital? (Nie, 2001; Bargh, 2004; Wellman, 2001) NO - reduce f2f time with others YES - enables new connections with similar interests and goals - allows weak ties to form, giving rise to bridging social capital - helps to keep and sustain dispersed networks - 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,

25 social capital and facebook (Ellison, 2007) N= 286 college students (MSU) #friends time attitudes scales for bridging & bonding capital 25

26 results: bridging social capital linear regression of bridging social capital scale from FB and other factors results: bonding social capital linear regression of bonding social capital scale from FB and other factors limitations: - only students of one campus - only self-reports 26

27 social capital in facebook: actual usage (Burke et al. 2010) N= 1193 Facebook english-speaking users (20 countries) + 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 (taken as a whole) credit: paul butler, duncan flickr (cc): M. Burke, C. Marlow, and T. Lento, Social Network Activity and Social Well-Being, in Proc. ACM CHI, Atlanta, Apr features extracted from facebook activity logs: general engagement mean std period: two months 27

28 features extracted from facebook activity logs: directed communication and content consumption mean std linear regression results 28

29 in summary FB network size is modestly associated with increased bridging & bonding social capital and reduced loneliness FB directed communication is modestly associated with increased bonding social capital and reduced loneliness FB consumption is modestly associated with reduced bridging social capital and increased loneliness credit: dani flickr (cc): what to remember the social media paradox facebook is not a utiliity.. yet it is a system that allows to study human behavior descriptive analysis of users four degrees of separation facebook is dynamic; has to be studied as such user motivations social grooming social capital 29

30 questions? 30