Ajith Abraham, Computational social network analysis : trends, tools and research advances (Dordrecht: Springer, 2010).
CH1. An Overview of Methods for Virtual Social Networks Analysis
지하철 노선도 , CD 표지 , Communication : 이모티콘 Discovery : Small World problem Insight : Social Network 음 .. 예제가 적절치 못해 -_-; 앞으로 4 가지 visualization technique 를 다루게 된다 . 1) graph, 2) matrix, 3) map, 4) hybrid
“ each node can represents an actor, single or group, or a topic and each link (arc) represents the connection between couples of actors or topics.” M. C. Caschera, F. Ferri, and P. Grifoni, “[27] SIM: A dynamic multidimensional visualization method for social networks,” PsychNology Journal 6, no. 3 (2008): 291-320.
Planar graph : edge 사이에 intersection 이 발생하지 않게 그릴 수 있는 graph. 발생하지 않게 그린 graph 는 plane graph or planar embedding of the graph 라고 한다 . J Bondy, Graph theory with applications (New York: American Elsevier Pub. Co., 1976). 135 p http://en.wikipedia.org/wiki/Planar_graph Planar Graph : 평면 그래프 “ 이 planar graph 는 몇 가지 좋은 특성을 가지고 있다 . 가장 중요한 속성은 모든 planar graph 는 sparse 하다는 것이다 . Euler 의 공식 (Euler’s formula) 은 Edge E 와 Vertex V 로 이루어진 Graph 는 | E| <= 3|V| -6 임을 밝혔다 . 즉 , Edge 의 개수가 linear 함을 보여주는 것이다 . 또한 모든 planar graph 는 vertex 의 degree 가 많아야 5 이다 . 그렇기 때문에 다른 graph 에서는 polynomial time 에 해결되지 않은 알고리즘이 planar graph 에 대해서는 매우 빠르게 동작한다 . 그리고 planar graph 의 subgraph 도 항상 planar 이다 . “ http://mybox.happycampus.com/yangpa09/645528
[22] Who Shall Survive? Nervous and Mental Disease Publishing
Relationship between actors Subgroups Characteristics of the Virtual Social Networks Spring-embedding (force-directed) algorithm 노드간에 힘이 존재하여 , 보기 좋은 형태로 산개 하는 그래프 . Bernes-Hut algorithm [ 논문 ] used to efficiently compute n -body (repulsion) forces and numerical integration routines are used to smoothly update screen positions. [Vizster 논문 ] community structures Newman's community identification algorithm [ 논문 ] it provides useful topology-based groupings fast enough to support real-time interaction. [Vizster 논문 ]
Left : Kamada-Kawai Algorithm Right : Vmap-layout Algorithm
“ The matrix-based approach associates the network actors with rows and columns; the matrix cell values identify social connections between actors.” M. C. Caschera, F. Ferri, and P. Grifoni, “[27] SIM: A dynamic multidimensional visualization method for social networks,” PsychNology Journal 6, no. 3 (2008): 291-320.
Row matrix or Row vector Column matrix or Column vector Square matrix : 정방 행렬 Identity matrix : 단위 행렬 Digonal matrix : 대각 행렬 Symmetric matrix : 대칭 행렬 Skew-symmetric matrix : 반대칭 행렬 Triangular matrix : 3 각 행렬 ( 그림은 상 3 각 행렬 )
“ newsmap,” http://newsmap.jp/ . “ The map-based visualization is suitable to show and organize large volumes of data and complex social networks data structures emphasizing textural or conceptual features of the visualization by shading, colours, labelling and icons.” M. C. Caschera, F. Ferri, and P. Grifoni, “[27] SIM: A dynamic multidimensional visualization method for social networks,” PsychNology Journal 6, no. 3 (2008): 291-320.
B. A. Nardi et al., “[25] Contact Map : integrating communication and information through visualizing personal social networks,” Communications of the ACM 45, no. 4 (2002): 89.
M. C. Caschera, F. Ferri, and P. Grifoni, “[27] SIM: A dynamic multidimensional visualization method for social networks,” PsychNology Journal 6, no. 3 (2008): 291-320.