The centrality of Social Network Analysis

As professor Chan said in the lecture, social network analysis is important in our daily life and
epistemological behaviors,Which study of social relations among a set of actors. It is a field of study -- a set of phenomena or data which we seek to understand.

"SNA can be defined as the mapping and measuring of relationships and flows between people, groups, organizations, computers, or other information- or knowledge-processing entities."

Social network analysis is the mapping and measuring of relationships and flows between people, groups, organizations, computers, URLs, and other connected information/knowledge entities. The nodes in the network are the people and groups while the links show relationships or flows between the nodes. SNA provides both a visual and a mathematical analysis of human relationships.

To understand networks and their participants, we evaluate the location of actors in the network. Measuring the network location is finding the centrality of a node. These measures give us insight into the various roles and groupings in a network -- who are the connectors, mavens, leaders, bridges, isolates, where are the clusters and who is in them, who is in the core of the network, and who is on the periphery?

There are three parameters tp identify key/central nodes in network.

DEGREE: How many people can this person reach directly?
Degree centrality
-A node's in or out degree is the number of links that lead into or out of the node
-Often used as measure of a node's degree of connectedness and hence also influence and/or popularity

BETWEENESS:How likely is this person to be the most direct route between two people in the networl?
Betweeness centrality
-The number of shortest paths that pass through a node divided by all shortest paths in the network
-Sometimes normalized such that the highest value is 1
-Shows which nodes are more likely to be in communication paths betwwen other nodes.

CLOSENESS:How fast can this person reach everyone in the network?
Closeness centrality
-the mean length of all shortest paths from a node to all other nodes in the network
-It is a measure of reach,i.e.how long it will take to reach other nodes from a given starting node
-Lower values are better when higher speed is desirable

Social network analysis methods provide some useful tools for addressing one of the most important,aspects of social structure: the sources and distribution of power. The network perspective suggests that the power of individual actors is not an individual attribute, but arises from their relations with others. Whole social structures may also be seen as displaying high levels or low levels of power as a result of variations in the patterns of ties among actors. And, the degree of inequality or concentration of power in a population may be indexed.

Power arises from occupying advantageous positions in networks of relations. Three basic sources of advantage are high degree, high closeness, and high betweenness. In simple structures (such as the star, circle, or line), these advantages tend to covary. In more complex and larger networks, there can be considerable disjuncture between these characteristics of a position-- so that an actor may be located in a position that is advantageous in some ways, and disadvantageous in others.

Group Epistemic Cognition in a Class Activity

In the lecture 6 of the Social Network course, our professor guided us to participant in a class activity, which divided in 2 parts. One part is the class activity one-A, which let us accomplish a task by ourselves. Another part is the class activity one-B, which forced us to finish the same questions in the form of group study. Professor let us to distinguish the differences of these 2 parts.

 

Class Activity One – A

1. What is the definition of Social Cloud?

A Social Cloud is a resource and service sharing framework utilizing relationships established between members of a social network.

2. What are the possible applications of a Social Cloud?

    A Social Computation Cloud

    A Social Storage Cloud

    A Social Collaborative Cloud

   A Social Cloud for Public Science

   An Enterprise Social Cloud

3. What strategies you have adopted in answering the above questions? 

Firstly, I read this paper carefully, and found some details about the definition of Social Cloud and the possible applications of a Social Cloud.

Secondly, I highlight the words and sentences what I think is the answer, but I don’t know whether the answer is right or not.

Lastly, I write down several questions I want to ask, e.g., what’s the meaning of the “volunteer computing project” in paragraph 8 and what’s the differences between Social Computation Cloud and Social Storage Cloud in terms of the photo storage?

 

Class Activity One – B

What cognitive processes have you gone through at: (1) cognition level, (2) metacognition level, and (3) epistemic cognition level?

When I finished the task individually I think I have gone through the cognition level and metacognition level. However, when I discussed the answer with group members, I think I have used all the three levels.

Because some opinions came from our members began to differ. Everyone put forward their own theory and comment on each other's answer. One of my group member modified my highlighted sentence and told me why I found the wrong answers. What’s more important, in the group I can ask some questions that I wanted to ask after I finished reading all the paper by myself. Group members were glad to answer my questions that they knew the answer. Maybe sometime we all have no ideas about someone questions. But we can figure out some ways to find the resource. If there’s no group discussion, I think I can’t find these answers so fast. At the same time, in the group I can catch the central meaning of this article more precisely.

 

So what is group epistemic cognition? I think it’s an ability to learn creatively. Groups of people can engage in activities such as mathematical problem solving and can accomplish intellectual achievements. At the same time, the online networks can provide active media for social group epistemic cognition where ideas grow through the interactions within groups of people.

 

Above all, I think group study is a good way to enhance our understanding of the knowledge no matter online network or in traditional room. Group epistemic cognition can demonstrated the importance of collaboration.