How to social scientists use link data (11 june2010)
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How to social scientists use link data (11 june2010)

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The author would like to thank Bernie Horgan, Rob Ackland, Jeong-Soo Seo, and Yeon-ok Lee for their helpful comments on an earlier draft. Part of this research was carried out during the author’s......

The author would like to thank Bernie Horgan, Rob Ackland, Jeong-Soo Seo, and Yeon-ok Lee for their helpful comments on an earlier draft. Part of this research was carried out during the author’s stay at the Oxford Internet Institute. During the preparation of final manuscript, this research is supported from the WCU project granted from South Korean Government. This paper has been presented at the 2010 International Communication Association conference held in Singapore. http://www.icahdq.org/conferences/2010/

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  • 1. WCU WEBOMETRICS INSTITUTE INVESTIGATING INTERNET-BASED POLITICSS WITH E-RESEARCH TOOLS Use of search engine data to understand Internet-based political and electoral communication? Dr. Han Woo PARK Associate Professor Department of Media & Communication YeungNam University 214-1 Dae-dong, Gyeongsan-si, Gyeongsangbuk-do 712-749 Republic of Korea hanpark@ynu.ac.kr http://www.hanpark.net Principal Investigator of WCU Project: Investigating Internet-based Politics with e-Research Tools. A paper accepted for presentation to the 2010 annual conference of ICA (International Communication Association) held in Singapore, http://www.ica2010.sg
  • 2. Abstract As link data become more available from search engines, the data can play an important role in understanding socio-political activities in cyberspace. Internet-based political and electoral communications conducted in Korea, where online communication is among the most well-established in the world. Advantage Disadvantage link data collected from link data have some search engines have weakness, such as several merits for reliability issues: internal political communication Two case algorithms are not made research, including in public and there are inexpensive access to inconsistencies among web resources and ease search engines. of use. Key worlds: case studies to draw conclusions about the use of link data drawn from Two search engine, search engines for research method, political communication, link analysis, social science purposes. online research method WCU WEBOMETRICS INSTITUTE INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 3. Introduction Web traffic is only one part of online communication. There are other significant communication behaviors on the Internet that could be captured by researchers using publicly available tools. The Myth of Digital Democracy, Hindman (2008) political and electoral These bits of online In this study, we are The Internet is communication is information produced mostly interested in growing at an undergoing a significant and inscribed via links examining and transformation because are explicitly or enormous Internet-mediated implicitly connected to evaluating the rate in terms communication has each other by topics of practices and trends of of recorded digital traces. rapidly become popular interest and have online political among government become a useful communication by officials, politicians, and resource for citizens. researchers. examining the ‘linking’ behavior involved. WCU WEBOMETRICS INSTITUTE INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 4. Introduction The Internet represents a massive storehouse of social networking data, enabling researchers to capture political communications by individual officials, politicians, and activists. This is particularly true in South Korea, where political participants almost always have online representation. Two case studies of Internet-based political and electoral communications conducted in Korea. Case 1. Examines the online characteristics of the 2007 presidential election in Korea. We analyze a substantial amount of link data obtained using search engines in order to understand their broader political implications. Case 2. Examines how search engine-based methods are useful in discovering connections among Korean legislators in the online social networking sphere in Korea. These cases reveal that link data collected from search engines have merits for political communication research. The following discussion looks at the pros and cons of search engines as research tools and the use of link data collected from search engines. WCU WEBOMETRICS INSTITUTE INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 5. Background Information and Relevant Literature The web is constantly growing in terms of content, search engines play the role of information intermediaries for the web, which has become an important part of public dialogue. In research analyzing the e-science landscape using statistics about individual keyword queries via Google, Meyer and Schroeder (2009) found that the search pattern for the term ‘cyberinfrastructure’ reveals which U.S. regions are deeply involved in national e- science projects, such as major supercomputing centers. Further, using Google-generated keyword activity data, Varian and Choi (2009) showed that public data from search engines helped improve economic forecasts for various industries, including automobile sales, home sales, retail sales, and travel behavior. Thelwall (2004) Search engines allow researchers to get materials from a much wider range of subjects than previously available through traditional library databases. One important contribution of search engines is the ability to retrieve relevant web-based materials using hypertext links, enabling researchers to gather and recombine information collected from the Internet. WCU WEBOMETRICS INSTITUTE INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 6. Background Information and Relevant Literature Elgesem (2008, p.239) argued that “search engines are objective in the sense that these engines try to be consistent with their own stated policies.” With respect to coverage and consistency, problems may occur due to the nature of the unstructured web. In other words, the lack of reliability may not be caused by the search engine. Science organizes, structures, and evaluates information to develop a systematic body of knowledge. It is up to the researcher to draw the appropriate conclusions, using his or her expertise, about the information gathered from the web using search engines. While search engines collect data from the entire web, finding the truth from the information is the business of academics (Caldas et al., 2008). WCU WEBOMETRICS INSTITUTE INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 7. Case 1. 2007 Korean Presidential Election Background Korea boasts the highest proportion of broadband users in the world, and there is a unique evolution of online culture in Korean cyberspace. The country’s impressive level of technological development includes a vibrant online communication environment. The online political climate during the 2007 Korean presidential election can be examined effectively using web-based data analysis. In particular, there were 12 candidates who ran for president and several parties were created in 2007 to support these candidates (see Table 1). The candidates and the parties had to compete against each other to win public attention, particular since it was difficult for citizens to differentiate their stances on issues. Particularly useful for web analysis was the fact that public opinion surveys could not be published within six days before the 2007 election. In 2002, surveys could not be published within 22 days of the presidential election. We will examine how the popularity of individual candidates and parties developed during the 2007 presidential election campaign in South Korea using web-based data collection. WCU WEBOMETRICS INSTITUTE INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 8. Background Table 1. Websites of Presidential Candidates and Parties Candidate Website Candidate’s Party Website Lee Myung-Bak (Lee MB) www.mbplaza.net Grand National Party (GNP) www.hannara.or.kr Chung Dong-Young (Chung DY) www.cdy21.net United New Democratic Party (UNDP) www.undp.kr Lee Hoi-Chang (Lee HC) www.leehc.org Independent Moon Kook-Hyun (Moon KH) www.moon21.kr Creative Party (CKP) www.ckp.kr Kwon Young-Ghil (Kwon YG) www.ghil.net Democratic Labor Party (DLP) www.kdlp.org Rhee In-Je (Rhee IJ) www.ijworld.or.kr Democratic Party (DP) www.minjoo.or.kr Huh Kyung-Young (Huh KY) Same as party site Economy & Republican Party (ERP) www.gonghwa.com Geum Min (Geum M) www.minnmin.net Socialist Party (KSP) www.sp.or.kr Chung Kun-Mo (Chung KM) www.bestjung.kr True Owner Coalition (TOC) www.chamjuin.or.kr Chun Kwan (Chun K) www.chamsaram.or.kr Chamsaram Society Full True Act Same as candidate site (CSFTA) Sim Dae-Pyeng (Sim DY) www.dpsim.co.kr People First Party (PFP) www.mypfp.or.kr Lee Soo-Sung (Lee SS) www.leesoosung.com People’s Coalition (PC) Same as candidate site WCU WEBOMETRICS INSTITUTE Case 1. 2007 Korean Presidential Election INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 9. Data collection Subject investigated: The web presence of all 12 candidates and their parties during the official campaign period of the 2007 Korean presidential election. Date: The online visibility of each party and candidate was measured with colink data, which refer to incoming links shared between any pair of candidates’ or parties’ websites. These data were collected at multiple points during the election period from search engine indexes. Acquisition time: Colink data were gathered in three-day intervals, 29 November - 17 December in 2007 (the election was held in 19 December 2007). WCU WEBOMETRICS INSTITUTE Case 1. 2007 Korean Presidential Election INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 10. Analytic technique The process of generating a colink matrix is as follows (for detailed procedures, see Thelwall, 2009). First, an input file, which lists a set of colink queries to retrieve webpages sending at least one link to a pair of website addresses under investigation, is made using a text editor program (e.g., NotePad). Second, a symmetrical website*website matrix is created. Third, the resultant sociogram reveals which sites are central and peripheral. Fourth, key social network measures are calculated to analyze the overall structure of colinks: clustering coefficient, geodesic distance, and degree centrality (For the detailed explanation of network metrics, see Wasserman & Faust, 1994; Park & Leydesdorff, 2009). WCU WEBOMETRICS INSTITUTE Case 1. 2007 Korean Presidential Election INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 11. Analytic technique As Park (2003) stated in his seminal article titled “Hyperlink network analysis: A new method for the study of social structure on the web,” link data can be examined using social network analysis. The clustering coefficient indicates the degree to which friends (in this case, neighboring websites) of a person know each other; average distance value shows the degree of separation on average between each (reachable) pair of websites in terms of geodesic distance that is defined as the shortest path. The average distance is often reported with an overall cohesion value between 0 and 1. Larger values indicate greater cohesiveness. Degree centrality is a basic and primary measure to indicate the position of a website based on its interconnections with other websites in a given network. Due to space limitations, only three websites used in this study were reported in Table 2. WCU WEBOMETRICS INSTITUTE Case 1. 2007 Korean Presidential Election INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 12. Findings The results from the colink data and its accompanying qualitative investigation indicate the following. The hyperlinked relations among the candidates and parties over time reflect their positioning in the electoral race and the general climate of offline politics. In Figure 1, squares represent candidates’ sites and circles represent parties’ sites. The thickness of the lines connecting them is drawn bigger in accordance with the number of external colinks directed to a pair of sites. WCU WEBOMETRICS INSTITUTE Case 1. 2007 Korean Presidential Election INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 13. Findings Since the snapshots taken in December 2007 display distinctive changes, we focus on these dates in the results section. On 2 December, we can see clearly that parties are clustered with other parties and candidates are closely linked with other candidates. However, 9 out of 20 sites were not included in the network. Isolated candidate and party sites are located in the upper left-hand corner of the diagram. During the initial stage of the campaign, online attention focused on major parties and candidates, as Figure 1 shows. Overall, the network structures among candidates and parties seemed to be loose. Figure 1: 2 Dec 2007 WCU WEBOMETRICS INSTITUTE Case 1. 2007 Korean Presidential Election INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 14. Findings From the network diagram captured on 11 December, it is clear that the Lee HC (leehc.org) website was successful in catching up with other major candidates’ websites. As a matter of fact, he became one of the major candidates. He took third position in the presidential race by gaining 15.1% of the total votes. But, he entered the race late relative to other major candidates and ran without support from a specific party. As seen in Figure 2, he was finally included in the user-driven networking zone. Another interesting finding on 11 December is the position of ijworld.or.kr (Rhee IJ’s site) and ckp.kr (CKP’s site). In the 2 December figure, ijworld.or.kr was only connected to the party site (minjoo.or.kr), but it later became linked with progressive candidate Chung DY’s site (cdy21.net). The reason is that Rhee IJ had been strongly urged by the public to give up his candidacy in support of Chung DY. In the case of ckp.kr, this website showed a dramatic turnaround as its candidate’s (Moon KH, moon21.kr) popularity increased. Figure 2: 11 Dec 2007 WCU WEBOMETRICS INSTITUTE Case 1. 2007 Korean Presidential Election INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 15. Findings Figure 3, captured on 17 December, shows that, at the end of the campaign period, a total of 14 candidates and parties joined the user-driven networks. As election day approached, the number of isolated sites noticeably decreased from 9 (2 Dec) to 5 (17 Dec), which reflected increasing online public awareness of the election. Two candidates, Lee HC (leehc.org) and Rhee IJ (ijworld.or.kr), seemed to be on their way to success because they were fully included in the network. President-elect Lee MB (mbplaza.net ) and his party (hanara.or.kr) were in the center of the candidate and party group networks, respectively. Overall, the figures show that as time progressed, link density increased. Figure 3: 17 Dec 2007 WCU WEBOMETRICS INSTITUTE Case 1. 2007 Korean Presidential Election INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 16. Findings In addition to the three figures, other network measures between nodes were examined, as summarized in Table 2. The clustering coefficient that measures the cohesiveness of the network was 2.581 in the beginning of the official campaign (2 Dec), but dropped to 1.777 two days before the election (17 Dec). Next, while average reachability scores in terms of geodesic distance between pairs show some fluctuation, cohesion values in parenthesis clearly indicate that the network became dense (0.215 -> 0.273 -> 0.346). Average distance values lengthened in accordance with the gradual influx of isolated sites into the network. Lastly, three websites in particular showed an increase in their degree centralities. Table 2. Network Measures of Colink Networks with Three Different Points Network measures 2 Dec 2007 11 Dec 2007 17 Dec 2007 Clustering coefficient 2.581 2.368 1.777 Average distance 1.564 1.821 1.681 (Cohesion value) (0.215) (0.273) (0.346) Degree centralities of sites ijworld.or.kr 0.158 0.263 0.684 leehc.org 0.000 0.053 0.263 ckp.kr 0.000 0.053 0.053 Note: Data were dichotomized for the calculation of clustering coefficient and geodesic distance values, and degree centralities were normalized for comparison across networks. WCU WEBOMETRICS INSTITUTE Case 1. 2007 Korean Presidential Election INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 17. Case 2. Cyworld Mini-hompies of Korean Legislators Background The sample for the social networking sphere (Figure 4) is drawn from the Cyworld mini-hompies (mini-homepages) maintained by members of the 18th National Assembly. Cyworld is a Korean web-based social networking service launched on 1 September 1999 . “Cy” means both “cyber” in English and “relationship” in Korean. Internet users form a buddy relationship with each other through a service called “mini-hompy,” where they can decorate their “home” and invite friends using a photo gallery, video clip, message board, guestbook, friend list, and personal bulletin board. It is similar to the U.S.- based Facebook and MySpace sites. In a study of blogs of Korean legislators, Park and Kluver (2009) stated that the mini- hompies are not only popular with Korean youth, but also with many older Koreans. Cyworld is Korea’s dominant social networking site, with 90% of young people in their 20s and 25% of the total South Korean population registered as users. According to the study, South Korean politicians have also begun to make significant use of blogs and mini-hompies to expand their “personal communities.” WCU WEBOMETRICS INSTITUTE Case 2. Cyworld Mini-hompies of Korean Legislators INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 18. Data collection As of 16 March 2009, 83 out of a total of 295 National Assembly members run their own mini-hompies. The distribution of the 83 members is as follows: 47 from the GNP (Grand National Party, the ruling party, Han-na-ra in Korean), 19 from the DP (Democratic Party, the major opposition party, Min-joo in Korean), 8 from the LFP (Liberty Forward Party, Jayu Seonjindang in Korean), 2 from the PPA (Pro-Park Alliance, Chinbak Yeondae in Korean), 2 from the DLP (the Democratic Labor Party, progressive party, Min-joo-no-dong in Korean), 1 from the CKP (Creative Korea Party, Changjo Hangukdang), and 4 independents. We obtained the members’ mini-hompy URLs through official websites and commercial search engines. We were interested in the legislators’ interpersonal social networking in cyberspace. However, it is difficult to trace personal relationship among politicians because “friends” on mini-hompies are confidential. Three datasets with respect to the status of legislators’ mini-hompies were collected: 1) date of creation, 2) number of visitors, and 3) frequency of bookmarking by other mini- hompy users. These data were manually collected. Legislators who did not indicate the creation date of their sites public were excluded. As a result, we collected data on links, creation date, number of visitors, and bookmarks for 70 Korean politicians. WCU WEBOMETRICS INSTITUTE Case 2. Cyworld Mini-hompies of Korean Legislators INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 19. Analytic technique The same procedures described earlier have been applied to this case study. Regarding social network analysis, betweenness centralities were measured in addition to degree centralities. While degree centrality measures a relational attribute of an actor in a network (e.g., popularity, activity, and prominence in the flow of information), betweenness is a useful index to measure the potential influence of the actor in controlling and coordinating communication. Additionally, we have examined the association between network centralities and traffic activities. WCU WEBOMETRICS INSTITUTE Case 2. Cyworld Mini-hompies of Korean Legislators INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 20. Findings Thirty out of 70 Cyworld-connected legislators were included in the colink network; 40 politicians operated isolated websites. Lines between the websites indicate the presence of colinks between mini-hompies, the thickness of lines indicates the number of colinks, and colors represent the different parties. The size of the label (that is, the politician’s web address) is in proportion to the number of bookmarks, and the size of the node corresponds to the number of visitors. The map clearly distinguishes relatively peripheral groups (sparely linked politicians) from central ones (densely connected politicians) in Korea. WCU WEBOMETRICS INSTITUTE Case 2. Cyworld Mini-hompies of Korean Legislators INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 21. Findings Table 3. Normalized Measures of Individual Politicians The network Name Cyworld_URL Degree Betweenness Visitors Bookmarks Party centralities and Kang GG kanggigap 28.986 0.005 119.36 0.21 DLP Kwon YG kwondlp 27.536 0 92.87 0.08 DLP traffic information Kim MS kimmoosung 14.493 0 4.98 0.00 GNP for the 30 Assembly Kim YS kimyoungsun1 42.029 3.649 19.76 0.02 GNP members’ mini- Kim UD kimeuldong 26.087 0 88.08 0.13 PPA Kim JP jinpyo415 28.986 0.005 41.04 0.04 DP hompies are Na KY KyoungOne 28.986 0.005 502.42 0.44 GNP presented in Table 3. KP npil2580 28.986 0.005 32.32 0.05 GNP Park GH ghism 42.029 3.649 4524.34 5.89 GNP Notes: Seo BS sbs8680 14.493 0 3.91 0.00 GNP Song YS peacekeeping 14.493 0 28.33 0.02 PPA http://www.cyworld Ahn HJ masanjun 14.493 0 7.35 0.00 GNP .com was omitted Won HY Won HR whywon21 wworld 28.986 28.986 0.005 0.005 9.28 86.71 0.01 0.17 DP GNP in front of the Yoo SM ysm21com 14.493 0 11.70 0.01 GNP URLs in the table. Yoo JB ilovegimpo 14.493 0 6.47 0.00 GNP Visitors and Lee KJ yeskj1 28.986 0.005 15.08 0.02 DP Rhee IJ ij21 28.986 0.005 17.96 0.02 Indy bookmarks were Lee HC chang2007 27.536 0 2726.29 1.34 LFP divided by the Chung MJ Chung Sk globalmj skchung21 28.986 28.986 0.005 0.005 87.14 23.07 0.19 0.03 GNP DP number of days the Chung JS jangseon 28.986 0.005 6.55 0.00 DP Cyworld mini- Cho KT boss110 28.986 0.005 138.22 0.13 DP hompies were in Joo SY doitnow304 14.493 0 59.64 0.03 GNP Chin SH sheechin 28.986 0.005 19.26 0.02 GNP existence. Cha MJ sosacha 28.986 0.005 26.40 0.01 GNP Han SK hsunkyo 14.493 0 53.54 0.11 GNP Hong JP jphong21 28.986 0.005 61.89 0.05 GNP Hwang WY hwangwygrace 28.986 0.005 8.44 0.01 GNP WCU Hwang JH uncinc 14.493 0 7.50 0.00 GNP WEBOMETRICS INSTITUTE Case 2. Cyworld Mini-hompies of Korean Legislators INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 22. Findings As seen in Figure 4, the network structure shows a clear butterfly pattern. There is one hub (ghism) that belongs to Park Gyun-Hye (Park GH, www.cyworld.com/ghism), the daughter of ex-president Park Jeong-Hee and one of two major GNP candidates (along with president-elect Lee MB) in the 2007 presidential race. Figure 4: Cyworld Mini-hompies of Korean legislators WCU WEBOMETRICS INSTITUTE Case 2. Cyworld Mini-hompies of Korean Legislators INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 23. Findings Table 4 demonstrates that the magnitude and direction of the association between several centralities and two other variables—visitors and bookmarks—are significantly correlated. Table 4. Pearson’s coefficient Betweenness Visitors Bookmarks Degree .572(**) .390(*) .420(*) Betweenness .572(**) .665(**) Visitors .945(**) ** Correlation is significant at the 0.01 level (1-tailed). * Correlation is significant at the 0.05 level (1-tailed). N=30 (Isolated politicians were excluded in this analysis) WCU WEBOMETRICS INSTITUTE Case 2. Cyworld Mini-hompies of Korean Legislators INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 24. Discussion and Conclusion This analysis of the linking patterns among Korean politicians’ websites reveals some interesting facets of how search engine data can be used to map Korean Internet- mediated political culture. Our findings demonstrate that online markers of political communication, in the form of hyperlinks, exhibit the significant characteristics that drive many other phenomena in Korean presidential elections: the networked practices of politics and affiliations among politicians. Questions that require further exploration include: 1)Can we trust available search engines, and, if not, what can we do about them? If we are able to gain access to the search process and how websites are ranked, can this problem be solved? 2) How do we deal methodologically with the complexity of Web 2.0 using current search engine mechanisms that do not properly index multimedia content? Do we need new search tools for Web 2.0? WCU WEBOMETRICS INSTITUTE INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 25. Lessons for Future Tracking and Mapping Research What are the lessons from this particular exercise for mapping and tracking online political communication in the future? First, some forms of political information exchange are difficult to study only using search engine results. Second, qualitative analysis is also necessary because every country has different web characteristics. Third, although we analyzed link data using social network measures and visualizations, this study is descriptive and topological. Fourth, the purpose of this article was to introduce social science readers to the methods of search engine-mediated data collection for political research using social network measures and visualizations. WCU WEBOMETRICS INSTITUTE Case 2. Cyworld Mini-hompies of Korean Legislators INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS
  • 26. WCU WEBOMETRICS INSTITUTE INVESTIGATING INTERNET-BASED POLITICS WITH E-RESEARCH TOOLS THE END Thank you for listening, and thank my assistants (Ting Wang) •Park, H. W. (2011 forthcoming). How do social scientists use link data from search engines to understand Internet-based political and electoral communication. Quality & Quantity •The author would like to thank Bernie Horgan, Rob Ackland, Jeong-Soo Seo, and Yeon-ok Lee for their helpful comments on an earlier draft. Part of this research was carried out during the author’s stay at the Oxford Internet Institute. •During the preparation of final manuscript, this research is supported from the WCU project granted from South Korean Government. (No. 515-82-06574). http://english- webometrics.yu.ac.kr