Lecture 21: 29th November 2019 Flashcards
Privacy and social networks continued
What is an identity element?
Pieces of information about subjects, such as people, which have the potential to profile and uniquely identify them.
What are the most important identity elements to keep secret?
Drivers licence number, national insurance(UK)/social security(US) number, and credit card number.
What identity elements are can identify ~ 60% of US voters?
Sex, current ZIP code, and DOB.
How many friends are required on social media sites in order to identify you?
8
What is Febelfin?
A Belgian regulator of the financial sector and banking.
What did Febelfin’s PSA demonstrate?
That using freely available tools online can collate information about people detailed and sensitive enough to seem supernatural.
What were some criticisms of social networks raised by Ishbel in this lecture?
replace the need for in-person interactions, so may make people worse at them; may be addictive.
What is SNA?
SNA = Social Network Analysis = the process of gathering, investigating, and assessing data from social networks and social media platforms and trying to understand them in terms of relationships.
What is group cohesion?
The strength of bonds between individuals in groups.
What is a clique?
A total (completely adjacent - connected) group of nodes on a social network graph. They will have shared views. Cliques on social media have shared views, beliefs, or opinions. Think echo chamber. Note if you can monitor one, since all connected, you can monitor them all.
Where in cliques are people most happy?
Those at the centre of them, with a reach of 3 degrees of freedom
What is a cluster?
A collection of individuals with dense friendship patterns internally and sparse friendships externally.
Does unhappiness cluster? Why might this be the case?
Yes. Maybe because they are in mental health groups and echo off each other, or have similar life experiences making their views and making them unhappy, have the same interests (e.g. emo music).
What is Metcalfe’s law?
The monetary value of a network is directly proportional to the square of the size of the network (no of nodes in it).
What were the findings of Correa et al?
- in general, extroverts, the less emotionally stable, socially anxious and lonely people, more neurotic people, and more affective people and those more open to new experiences use social media significantly more
- emotionally unstable men used it significantly more than emotionally stable men but the same is not true for emotionally unstable women
- lonely and socially anxious people use social media to try their real-world problem of being lonely
- women place more value on connections and community than men who want to seem great themselves
How can you mathematically define the network core?
The node or nodes in a network for which the product of the in degree and out degree is highest: number of inbound and outbound vertices.
What is a triad?
A clique of 3 nodes.
What is distance?
The minimum number of the edges in the shortest path between two nodes.
What is reach?
The number of people who will view a social media post.
What is betweenness?
A representation of how often a node is a bridge: the proportion of the number of times a given node is on the shortest path or paths between each other pair of nodes other than the given node.
What is closeness?
How “close” a node is to others. Closeness = 1 / (mean length of shortest paths from that node to all others)
What is degree?
The number of nodes a given node is connected to.
What is a hub?
A central node, connected to all (or many) others, as in a star computer network.
What is a bridge?
A node or nodes connected to multiple cliques or clusters and form connections between them.
What is Bentford’s law?
It is an observation about the frequency distribution of leading digits in many real-life sets of numerical data. It can be used to analyse the distribution of digits in numeric data to assess whether it is true or not: can see fake data from outlying distribution of digits. This is how Greece was found to have faked financial books when joining the Eurozone.
What SNA research did Alex Voss do?
He analysed how (false) rumours spread during the London riots by classifying tweets supporting and debunking it and how the distribution changed over time, and then visualised them.
What does centrality mean?
Within a clique or cluster.
