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Ties Strength
Carlos FigueiredoPrograma Doutoral Media Digitais
Universidad do Porto 2016
How my tie with others affect me?
Imagine a room where you and some friends are talking with each other.
What is the effect when a friend of a friend, that is not from your social network, brings information, a news, etc.?
What happens when you talk with a close friend that usually is contacting different people from distant places and travelling around?
How is that my location in a social network regarding to others affect me?
The Strength of Weak Ties
Mark Granovetter creater of the concepts:
Strong tiesWeak ties
Professor in the School of Humanities at Stanford.
Research areas: Social foundations of the economy.
STRONG TIES WEAK TIES
Granovetter argues that weak ties serve primarily to build local bridges between groups of actors who otherwise would be isolated, which justify the strength of the weak ties (the richness of communication).
So, the weak ties help to the information flow through different social circles (strong ties).
Granovetter 1973
Granovetter was concern about how micro-level interactions relate to macro-level patterns.
And so, how interpersonal networks create such micro-macro bridges.
Granovetter 1973
Intuitive definition for the “strength” of an interpersonal tie
“The strength of a tie is a (probably linear) combination of the amount of time, the emotional intensity, the intimacy (mutual confiding), and the reciprocal services which characterize the tie.”
Granovetter 1973
e.g.If A B 60% of the time, and in the same way, if A C 40% of the time, theoretically B and C would be together 24% of the time.
Strong ties
B and C will establish a dyadic relationship being that based in a "psychological strain" that "push" B and C to be friends, since B it’s friend with A and A with C
theory of triangle
Transitivity may be regarded as a function of the strength of ties, rather than a general feature of social structure.
Granovetter 1973
All bridges are weak ties. No strong tie is a bridge.
Given a strong tie a-b, if a has another strong tie to C, than a tie exists between c and b, so that the path a-c-b exists through b and c; hence, b-c is not a bridge.
A strong tie can be a bridge, only if neither party to it has any other strong ties.
Weak tiesbridges
Granovetter 1973
Weak ties Relevance
“Intuitively speaking, this means that whatever is to be diffused can reach a larger number of people, and
traverse greater social distance (i.e., path length), when passed through weak ties rather than strong.”
e.g. Rumors
Hysteria incident
Small Worlds
diffusion process
Granovetter 1973
If the rumour spreads strong ties moves few clicks
(bridges won’t be crossed)
If ones tells a rumour to all his closed friends, then is probable that each person will hear the same rumour more than ones.
diffusion process
Weak ties Relevance
Granovetter 1973
Through weak ties bridges other social circles
diffusion process
Weak ties Relevance
Granovetter 1973
The hysteria incident
Five of the six workers earliest affected were considered as socially isolated, whether compared with other workers
“Only 1 of the 6 is mentioned as a friend
by anyone in our sample.”
(Kerckhoff and Back, 1968)
diffusion process
Weak ties Relevance
Granovetter 1973
By sending the booklet, the participants wrote if the receptor was a "friend" or a "acquaintance".
small worlds
diffusion process
Weak ties Relevance
Granovetter 1973
12
small worlds
diffusion process
BookletWeak ties
Relevance
The "acquaintances" were more effective in
bridging social distances.
Granovetter 1973ego networks
Weak ties Relevance
Ego has a collection of acquaintances
Few of the acquaintances know one another
Acquaintances have close friends forming a social circle, but one different from Ego's
Ties that make bridges are the channels through which ideas, influences, or information socially distant from ego may reach him.
Granovetter 1973
SWT
With the assertions about weak ties and bridges, and with his study about labor-market, Granovetter conceives the theory of the
"strength of weak ties"
Granovetter 1973
Should tie strength be developed as a continuous variable?
SWT
Is it linear (continuous) or discrete (disconnected)?
The Strength of Weak Ties
Mark Granovetter
A Network Theory Revisited(1983)
Granovetter 1983
Individuals with few weak ties "will be deprived of information from distant parts of the social system and will be confined
to the provincial news and views of their close friends."
SWT
Granovetter 1983
Empirical study of recent job changers (Granovetter 1974)
“Weak ties have a special role in a person's opportunityfor mobility".
Information arrives more through weak ties (27,8%) than through strong ones (16,7%).
SWT
Granovetter 1983
Clarifying when weak ties is an advantage
"weak ties are more efficient at reaching high-status individuals" (p. 207).
Weak ties are an advantage in the job seeking high-status individual (more contacts outside of the group)
weak ties do bridge social distance
“in lower socioeconomic groups, weak ties are often not bridges but rather represent friends' or relatives'
acquaintances”
SWT
Granovetter 1983
‘Digging’
Stronger the tie between two people, the greater the extent of overlap in their friendship circles
(Granovetter 1973).
"evidence suggests that local bridges tend to be weak ties because strong ties encourage triadic closure,
which eliminates local bridges“ Friedkin (1980, pp. 415- 417).
SWT
Granovetter 1983
Weak Ties and Social Organization
Judith Blau (1980) about the integration in a children's psychiatric hospital in New York City, argues that the integration can only be understood by considering the role of an extensive network of weak ties.
200 labours serving severely impaired children. Difficult treatments with uncertain outcomes. but, contrary to comparable institutions, there is not a high staff
turnover, neither a low morale.
Several subnetworks overlaps extensively with many others through the weak ties that serve bridging functions.
SWT
Granovetter 1983
Do these studies (1973-1983) show that the argument is empirically verified?
Does all weak ties serve the functions described in SWT?
SWT
In the footsteps of Granovetter intuition
Karen E. Campbell
Measuring Tie Strength(1984)
Peter V. Marsden
Research Interests: Social organization, especially formal organizations and SN
Research Interests: Gender InequalityOccupations and Professions, and SN
Edith and Benjamin Geisinger Professor of Sociology, Dean of Social Science, and Harvard College Professor
Associate Professor Senior Associate Dean for Undergraduate Academic Affairs, College of Arts & Science at Vanderbilt University
Measuring Tie Strength
Aim:
Measure the concept.
Identify if different indicators that have been used to measure tie strength covary with other variables in similar ways.
Examine the question of whether specific measures of tie strength are contaminated by other features of dyadic relationships.
Aim of the study
Indicators: time spent in the relationship, and the intensity, intimacy – mutual confiding - and reciprocal services within the tie.
Measuring Tie Strength
Three cross-sectional surveys.
Respondents were asked to identify their three closest friends, to report characteristics of these persons (age, occupation, religion, and so on), and to describe various features of these relationships.
Surveys:
Year of 1965-66 in Detroit Area.
Year of 1971 in the West German community of Altneustadt.
Year of 1974-75 in Aurora, Illinois
5,987 potential relationships analysed (in total).
Data
Measuring Tie Strength
Indicators: the ones defined by Granovetter.
Predictors: representing the foci on which a tie may be centered; indices of the social distance bridged by a tie.
Indicators: closeness, duration, frequency, breadth of discussion topics, and confiding.
Predicators: neighbor, co-worker, and kinship statuses, overlapping organizational memberships, differences in occupational prestige and years of education.
Measures
Measuring Tie Strength
Strength is a unidimensional unobserved concept or "point variable" intervening between its
predictors and its indicators.
The Measure Model
Measuring Tie Strength
Frequency is contaminated by neighboring (neighbors tend to see one another more frequently than non-neighbors).
Time spent in a relationship-duration and frequency of contact - badly contaminated by measures of foci around which ties may be organized (e.g. family).
The combined ability of the predictors to account for strength is limited.
Conclusions
Measuring Tie Strength
Closeness is the best indicator of tie strength(measure of the emotional intensity of a tie)
Conclusions
Measuring bridging factors
How to measure bridging factors?
Granovetter’ (1973) theory does not explain. Weak ties can be regarded as a proxy for disconnected alters.
New approach! Burt’ (1992) theory does.
What is the bridging factor on Burt’s theory?
Structural holes are the causal mechanism for bridging (factor), Not the tie strength (weak ties).
What says the theory?
Individuals that span structural holes are better informed of opportunities (less redundant information).
Bridging is measured calculating the spanning function by constraint.
Constraint is the degree of redundancy of individuals' contacts.
Both are related with the same kind of consequences:
Novel information delivered through bridging ties (Borgatti and Lopez-Kidwel 2011).
Present a mechanism on how new information can be accessed and delivered.
What is common to both theories? on bridging
Summarizing and Concluding
Structural bridges are transfer channels of material and nonmaterial resources that give access to new information, novelty, opportunities or better resources, through:
Weak ties (Granovetter 1973)
Closeness is the best indicator of tie strength
Structural holes & low constraint (Burt 1992)
Assertions from scholars
There is a relationship between bridging assumptions and a low redundancy in the flow of information (McEvily et al., 1999)
it may favor innovation (Ruef, 2002);
create a positive impact on individual creativity (Fleming et al., 2007; Sosa, 2011).
(…)
Stop!
Who said that receptors perceive the information delivered through a structural bridge as novelty?
Comparing both theories, what is the result for recipients? Would be the same?
Therefore, how accurate is the assertion that through bridging ties is there a delivery of novelty?
1st Study: Emotional perception
Surprise is identified as the emotional state related with the evaluation of novelty (e.g. Scherer 1984; Smith and Ellsworth 1987).
Surprise is an adequate measure of the improbability of a particular event, which is to say novelty detection (e.g. Strange et al.
2004).
1st: How to confirm the perception of novelty?
Analyzing the information flow delivered through structural bridges in order to introduce novelty on the receiver’s side
Findings: Positive relationship between surprise and both bridging factors
Bridging factors
Tie strength(weak ties)
Structural holes(Non-redundant connections
spanning structural holes)
Novelty perceived
Novelty delivery
Surprise response
PROXY
[Sender] [Receiver]
2nd Study: Central nodes
Centrality measures e.g. (Freeman, 1979) Betweeness; Closeness; Degree.
2nd: STRUCT. HOLES + SURPRISE IN CONTENT SELECT. IN SN
Analyzing the relationship between sender’s network position (i.e., structural bridge and Centrality, i.e., popularity) and receiver’s content selection and the strength of the tie.
Findings: No association! Content selection is strongly associated with surprise response
Network DimensionsBridging factor
• Structural holes
Strength of the tie (sender and receiver)
Content selection
Network centrality• Degree • Betweeness
Sender Receiver
ExposureContent production (publishing)
http://www.sciencedirect.com/science/article/pii/S0747563215003787
3th Study: Homophily in Social Networks
Birds of a feather flock together (McPherson et al., 2001)
Lazarsfeld & Merton (1954) distinguished two types of homophily:
status homophily: sociodemographic dimensions that stratify society e.g. ASCRIBED CHARACTERISTICS: race, ethnicity, sex, or age, and ACQUIRED CHARACTERISTICS: religion, education, occupation, or behavior patterns.
value homophily (or influence): internal states presumed to shape our orientation toward future behavior.
3th: PERSONAL ATTRIBUTES AND BRIDGING TO DEFINE COGNITIVE DISTANCE
Investigate the optimal cognitive distance…
Findings: The OCD can be characterized by bridges of weak ties and gender differences.
Bridging factors
Tie strength
Structural holes
Novelty delivery
SENDER RECEIVER
Personal attributes
HomophilyDemography Attitude
Music genres
Emotional reaction to
music genres
Political views
Cognitive Distance
Novelty perception
Surprise response
PROXY
Once upon a time…
EMOTIONS AND RECOMMENDER SYSTEMS:A SOCIAL NETWORK APPROACH
https://www.researchgate.net/publication/273456985_Emotions_and_Recommender_Systems_A_Social_Network_Approach
SOCIAL DATA ON RECOMMENDER SYSTEMS
Amplifying personalization performance…
Massive quantities of data from SN.
…it may generate users’ dissatisfaction and a new kind of constraint. Why?
SOCIAL ECHO CHAMBER EFFECT
Social data may create a Social Echo Chamber Effect
People end up trapped inside their – usual – social bubble of information.
Increases conformity, reduces the opportunity of accessing
novelty, creates lack of diversity in users’ viewpoints.
DATA BASED ON USERS’ PAST ACTIVITIES
USER “A”
Recommender system
ONLINE PAST ACTIVITIES
Online Social Networks
“Low” cognitive distance
SOCIAL DATA
Basing the improvement of personalization following principles of homophily…
Users’ representation in the network
BENEFITING FROM SOCIAL DATA[Research Question]
How to use social data and avoid the Social Echo Chamber Effect?
USER “A”
Recommender system
ONLINE PAST
ACTIVITIES
Online Social Networks
“Low” cognitive distance
SOCIAL DATA
“Higher” cognitive distance
Optial cognitve distance
DISCUSSION … the findings show that we can use social data…
SOLUTION AND THREATS… …
DEMOCRACY / TOLERANCE: People are being separated by opinion clusters).
CONFORMITY: Lack of “natural” freedom to access novel information.
COGNITIVE: People’s ability to interpret surrounding reality is diminished.
“FLUFFY” INNOVATION: The rush to consume people's time and attention can reduce the added value of some technologies to society.
CONCLUSION
The performance of social network-based
recommender systems can be improved
through social data conceived from
differences in gender and central nodes
defined by network bridges of distant ties
spanning non-redundant structural holes.
Thank you!
Carlos Figueiredo
Comments are welcome…
Birds of a feather flock together