Introduction

1. A longitudinal analysis of blog linkages among South Korean politicians Han Woo PARK, Ph.D.Assistant ProfessorYeungNam UniversityKorea (South)parkhanwoo@hotmail.com http://www.hanpark.netThis is in collaboration with Randolph Kluver at Texas A&M University, USApresented at the international conference of NetSci 2007, May 22-25, 2007, New York City, USA. http://www.nd.edu/%7Enetsci/index.html

2. Introduction • The Internet has become an important communication channel for politicians because of the power of relational networking • This study examines the online network relationships among political actors on cyberspace over a period of time

3. Trends of previous research • One approach has been on the content features of blogs, as a form of expression • The second approach takes a more network-oriented method using link data • However, little research has done on what impact the changing network structures might reshape network properties at an aggregate level

4. Issues in the use of political blog • Cass Sunstein (2001, 2004) • The process in which messages on cyberspace are exchanged and filtered brings about a ‘balkanization,’ or fragmentation, among people along interest lines or other socially defining characteristics

5. Issues in the use of political blog • Early studies (Ackland, 2005; Adamic & Glance, 2005) on political blog have produced results that generally confirm Sunstein’s claims about the Internet’s fragmenting effect

6. Issues in the use of political blog • In contrast, Hargittai, Gallo, & Kane (2005) • While polarization theory is useful in explaining blog-mediated social communication • It was also true that cross-linking across ideological borderline was happening • Also found that the divide did not tend to grow greater over time

7. Gap in literature review • Most of the previous research has looked at blogs only at a specific point in time, with little attention paid to the evolution of the online networks • Another gap is that little research has done on blogs maintained by “politicians”

8. Research question • How do the network properties of the Korean politicians’ blogosphere change over time? • Specifically, does the network undergo any significant changes that would suggest a longer term impact upon mediated politics in South Korea?

9. Sample and data collection • 17th National Assembly members • The ruling Uri Party (Uri) • The major opposition Grand Nat’l Party (GNP) • Two minor opposition parties and others • The Democratic Labor Party (DLP) • The Democratic Party (DP) • Others (e.g., a few independents)

10. Sample and data collection • During early July of 2005 and early November of 2006 respectively • In 2005, 107 blog-owning members were taken and 125 members in 2006 • As supplemental data, we interviewed politicians who have posted hyperlinks to at least one other Assembly member on their “blogrolls” (N=51)

11. Figure 2. Dendrogram of clustering results

12. Figure 2. Dendrogram of clustering results

13. Centrality: Individuals’ positions • The opposition GNP has a higher centrality ratio of its members and less isolates than the ruling Uri party in two years • In 2006, 21 out of 31 indegree isolates are from Uri party, and only six GNP isolates

14. Centrality: Individuals’ positions • The bloggers from the “minor” opposition also demonstrated poor network centrality • Compared to other minor players, half of the DLP members maintained blogs and they are relatively well connected over time

15. Change in group properties • The indegree pattern was by and large consistent across years but the outdegree pattern shows a moderate change • The maximum value of indegree in 2006 is 26, down from 30 in 2005 (-13.3%) • In the case of outdegree, the maximum value of the year 2006 is much less than that of previous year (53 -> 41, -22.6%)

16. Change in group properties • The total number of blogging members has increased from 107 to 125 • This implies that blog has been a part of general-purpose technologies for online communication

17. Distributions of degree centralities of 107 politician blogs in 2005

18. Distributions of degree centralities of 125 politician blogs in 2006

19. Change in group properties • Although the number of blogging Assembly members stayed roughly consistent, the network has become sparser, less integrated, and decentralized over time • Network density decreased from 0.07 to 0.04, indicating a decline of 37.39 percent

20. Change in group properties • As the average number of hyperlinks connections has decreased and the number of isolates has increased, integration among members has been weakened • Centralization also showed much change overtime, as a few hub members are disappearing

21. Change in group properties • These changing topographies reflect different communication practices • Politicians become less enthusiastic about using blog in order to make a tie with others • Our interviews reinforced our finding that politicians are gradually turning away gradually from blogs to mini-hompies, or to put a priority on official websites

22. Changes from 2005 to 2006

23. Network diagram • The map clearly partitions relatively peripheral groups (e.g., a set of isolates) from central ones in South Korea • Interestingly, the two major parties, the ruling Uri Party and the opposition Grand National Party, had clearly delineated networks among their members

24. Block modeling over time • The group density of 2006 for the ruling Uri party network jumped down to 0.018 from 0.026 in 2005 • Group density of the GNP also fell to 0.128 (2006) from 0.187 (2005) • This means that blogs did not strengthen a sense of being a ‘closed-network’ community over time

25. Block modeling over time • In relation to the deepening divide, there is only one cross-connection between Uri and GNP in 2005 • In 2006, the number of connections from Uri to GNP had increased to 10 and the frequency of reverse linking (GNP -> Uri) had gone to 3 in 2006 • The number of cross-links has slightly increased over time

26. N = 38 Density = 0.026 Link Sum = 36 N = 63 Density = 0.187 Link Sum = 731 N = 5 Density = 0.2 Link Sum = 4 Network diagram in 2005

27. N = 49 Density = 0.018 Link Sum = 42 N = 5 Density = 0.2 Link Sum = 4 N = 69 Density =0.128 Link Sum=599 Network diagram in 2006

28. A Scale-free network? • A characteristic of a scale-free network • A small number of sites receive the majority of hyperlinks and most sites receive very few hyperlinks • The number of hyperlinksper site has a power law distribution • The top 1% of sites attracted more than half of the hyperlinks

29. Change in group properties • We did not see the characteristic signature of a power law distribution from inlink connectivity among South Korea’s politician blogs but there may be some characteristics from outlink distribution • The outlink distribution in log-log scale is weakly fitted to the tail of a power law distribution when compared to real tails

31. Power law analysis in 2006 A characteristic of a power law distribution? A small number of site receive the majority of links and most sites receive very few links • Indegree distributions in linear scale plot in 2006 • Indegree distributions in log scale plot in 2006

32. Power law analysis in 2006 • Outdegree distributions in log scale plot in 2006 • Outdegree distributions in linear scale plot in 2006

33. Thanks for your attention ! • Interesting & growing area • Promising approach • New Media & Society Lab at YeungNam University in S. Korea • * Website: http://www.hanpark.net • * E-mail : parkhanwoo@hotmail.com • Many thanks to my assistants!