Social Networks Analysis Week 1

2 TED Talks about SNA The Hidden Influence of Social Networks How Social Networks Predict Epidemics https://www.ted.com/talks/nicholas_christakis_how_s ocial_networks_predict_epidemics

Opview http://www.opview.com.tw/

Edge/Link/Relationship Vertice/Node Edge/Link/Relationship A B C Clique Social Network

A Simple Social Diagram Nodes/Roles Relationships Directed/Undirected One Way/ Two Way Positive/Negative Selt-Defined A Simple Social Diagram

Social Network Analysis SNA

Terms/專有名詞 Social Networks A Description of Relationship Between Items (human, animal, etc.) A social network is a social structure to describe social relations (wikipedia) Social Networking Creating Social Networks or connecting people Online Social Networking Creating Social Networks or linking people via online environment (email, MSN, Line, WhatsApp) Social Networking websites Platforms for Social Networking (Facebook, Plurk, twitter) Social Networks Analysis Analysis the relationships of social networks Social Networks Mining Applying the techniques of data mining to analyze social networks Social Computing All applications related to social~

What is SNA? A set of mathematical and statistical techniques for handling relational data For identifying the structural properties of sets of relations (i.e. of networks) And for visualizing and describing networks Social scientific origins in: sociology, anthropology, social psychology Mathematical bases in: graph theory, matrix algebra and (increasingly) statistics There is an increasing dialogue with physics, maths, computer science, informatics

Cross-Fields Research

fROM sociology TO cOMPUTER sCIENCE Sociologists only focus on small social networks 50~100 nodes in a social network The advent of Internet communications has greatly increased SNA’s popularity Computer & Information Technologies become essential tools for SNA (Churchill & Halverson 2005)

sna measurements Relational Data From Social Data to Relational Data Nodes & Ties Dyad Triad Subgroup Group Degree Centrality and Power Density Path Length & Neighborhoods Small World Clustering Coefficient Structural Hole Clique

Relational Data

From Social Data to Relational Data

From Social Data to Relational Data Collect Social Data Identify the relationships Identify the weights of each relationship User matrix Network Graph Measurements

Six Degrees of Separation The experiment: Random people from Nebraska were to send a letter (via intermediaries) to a stock broker in Boston. Could only send to someone with whom they were on a first-name basis. Among the letters that found the target, the average number of links was six. 六度分隔理論 Six Degrees of Separation

Small-World Most pairs of nodes seem to be connected by a short path through the network (Six degrees of separation) Average path length (L): Mean path length between nodes in the network Diameter (D): Maximum path length between nodes in the network Small-world implies that spread of information will be fast

Six Degrees of Separation “Everybody on this planet is separated by only six other people. Six degrees of separation. Between us and everybody else on this planet. The president of the United States. A gondolier in Venice… It’s not just the big names. It’s anyone. A native in a rain forest. A Tierra del Fuegan. An Eskimo. I am bound to everyone on this planet by a trail of six people…” Six Degrees of Separation

sonam Applications Marketing & E-commerce Target Marketing Collaborative Recommendation Terrorist & Crime Detection 911 Network Ipswich’s Jack the Ripper, England 2006 Medical Network Finding Blood Organ Knowledge Management Sharing (Finding Knowledge) Innovation

sonam Applications Learning Organizational Social Network Analysis Optimice Politic & Election Academic Social Networking Family Tree Game AI On-line Game Game with Social Network (Game 2.0) Second Life And Much More…………………