Proceedings Template

Expressing Social Relationships on the Blog through Links and Comments

Noor F. Ali-Hasan

Microsoft

1065 La Avenida Street

Mountain View, CA 94043

(650) 693-1925

noor.ali-hasan@microsoft.com

Lada A. Adamic

School of Information

University of Michigan

1085 South University Avenue

Ann Arbor, MI 48109

(734) 615-2132

ladamic@umich.edu

Abstract

Blogs, regularly updated online journals, allow people to quickly

and easily create and share online content. Most bloggers write

about their everyday lives and generally have a small audience of

regular readers. Readers interact with bloggers by contributing

comments in response to specific blog posts. Moreover, readers

of blogs are often bloggers themselves and acknowledge their

favorite blogs by adding them to their blogrolls or linking to them

in their posts. This paper presents a study of bloggers‟ online and

real life relationships in three blog communities: Kuwait Blogs,

Dallas/Fort Worth Blogs, and United Arab Emirates Blogs.

Through a comparative analysis of the social network structures

created by blogrolls and blog comments, we find different

characteristics for different kinds of links. Our online survey of

the three communities reveals that few of the blogging

interactions reflect close offline relationships, and moreover that

many online relationships were formed through blogging.

Keywords

blogs, social networks, information visualization

1. Introduction

During the past several years, blogging, the keeping of a regularly

updated online journal interspersed with hyperlinks and

photographs, has emerged as a trendy yet powerful form of

computer-mediated communication (CMC). Blogs enable

individuals and organizations to quickly and easily share

information and links with a large set of readers. It is estimated

that 7% of U.S. adult Internet users, approximately eight million

people, have created a blog or online journal and 27%, or 32

million people, read blogs [23]. Far from being a phenomenon

concentrated in the United States, blogs are popular across the

globe [1, 2, 17].

Despite the large number of potential blog readers, only

a small fraction of blogs, known as the A-list blogs, command a

large portion of site traffic [14]. Most bloggers write about their

everyday lives and generally have a small audience of regular

readers [18]. Some of these readers interact with bloggers by

contributing comments in response to specific blog posts.

Moreover, readers are often bloggers themselves. They may list

the blogs they read in their blogrolls - lists of links to other blogs

placed in the sidebars of their own blogs. They can also create

links to other blogs and websites in their posts; we refer to these

links as citations. Citations within a blog post are usually used to

point out content on another blog or to refer to another blogger.

Receiving blogroll links, citations, and blog comments is a sign of

the blogger‟s popularity. Rather than being a one-sided expression

of interest, the relationships that bloggers have with one another

are often mutual. Moreover, bloggers tend to frequent the same

blogs and build relationships with bloggers that share similar

interests [13]. These cliques are often referred to as blogospheres,

sets of highly linked and intertwined blogs.

In examining the social structures created by blogrolls

and blog comments, it is unclear how these relationships and

social networks were formed. Did blog networks emerge due to

blogging or are these blogospheres merely representations of real

life social networks? In other words, do blogs help facilitate the

formation of new friendships or do they help preserve existing

relationships in the real world? Furthermore, do blog comments

and blogroll links represent different levels of relationship

intimacy? Understanding the answers to these questions will offer

a more complete picture of the social dynamics of blogging and

how individuals manage their virtual and real life relationships.

In addition, these insights may have implications for increasing

participation in online communities and computer-supported

cooperative work (CSCW) systems.

While previous studies have evaluated the impact of the

Internet on social behavior and examined the social network

structures of the blogosphere, here we draw a connection between

blogging and real life social networks. In order to do so, we

survey three blog communities who identify themselves with three

different geographical locations: Kuwait, Dallas/Fort Worth, and

the United Arab Emirates. We find that blogging relationships do

not reflect close real-world ties. Within each community, social

networks corresponding to different kinds of linking behavior -

blogrolls, citations, and comments - reflect different kinds of

interaction. We also observe differences across the communities

in measures of cohesion: reciprocity, density, and degree of

interaction with blogs outside of the community.

2. Related work

2.1 Computer-mediated communication and

relationship rormation

An overwhelming number of studies have shown that Internet use

can help individuals in developing and sustaining relationships.

Kraut et al. found that Internet use had a positive impact on

communication and social involvement [15]. Wellman points out

that the Internet enables individuals to maintain existing social

ties and develop new social ties with others sharing similar

interests [25]. He also argues that “the more contact people have

online, the greater the impression they make on each other.”

ICWSM’2007 Boulder, Colorado, USA

McKenna et al. conducted surveys of online newsgroup posters

that showed that some close online relationships naturally

progress to face-to-face interactions and that a majority of those

surveyed experienced an increase in their social networks due to

online interactions, regardless of the size of their social networks

[21].

Based on these previous results, we hypothesize that

blogging should enable people to develop new relationships

online and sustain and strengthen existing relationships in real

life. Indeed, preliminary ethnographic research of bloggers has

shown that blogging is a highly social activity. Nardi et al. found

that many people start blogging at the urging of friends and

continue to blog to avoid disappointing their readers [22]. Of the

motivations for keeping a blog, they found that three of them

(“update others on activities and whereabouts[,] express opinions

to influence others[, and] seek others‟ opinions and feedback”)

involved communicating with others. They also found that

communication sometimes extends to other media, including

email, instant messaging, and face-to-face conversation, which is

a trend we will follow up on in our study.

Most similar to our current study, Marlow[20]

conducted a large scale survey of over 35,000 blogs, gathering

their demographic information, motivations for blogging, and

communication frequency with individuals they linked to. Unlike

our present study, Marlow did not identify or compare different

communities, but he did extensively employ social network

analysis to characterize the linking patterns of hundreds of

thousands of blogs.

2.2 Blogs as social networks

Social network analysis is the quantitative study of the

relationships between individuals or organizations [24]. Social

network analysts represent relationships in graphs where

individuals or organizations are portrayed as nodes (also referred

to as actors or vertices) and their connections to one another as

edges (also referred to as ties or links) [24]. By quantifying social

structures, social network analysts can determine the most

important nodes in the network [24].

Applying social network analysis methods to the

blogosphere has revealed interesting findings about how

individuals share information and interact socially online. For

example, the linking patterns of blogs can be used to predict paths

of information flow through the blogosphere [6, 12]. Adamic and

Glance looked at the network structure of political blogs during

the 2004 U.S. Presidential election and found that the linking

patterns between conservative and liberal blogs formed two fairly

separate communities [5]. Moreover, Herring et al. found that

blogs that link to each other and are part of the same community

have a tendency to mention one another in blog posts and to

communicate with one another through comments [13]. These

citations between blog pairs occurred “on multiple occasions,

suggesting the existence of a relationship between them, not just a

one-time exchange.” Several studies proposed different measures

of network structure to identify and extract such communities

[11, 16, 19], and it is these structural measures that we turn to in

the next section.

3. Community structure

Our study focuses on three blog communities, each with a central

site containing a curated listing of blogs. For simplicity, we define

membership in a community simply by whether a blog was listed

on one of the three sites. The Kuwait and DFW communities were

selected because of the contrast in culture they represent. UAE

blogs were included so that we could compare the features of the

Kuwait community with another small Middle Eastern nation. The

sets of blogs were of different sizes, with 65 UAE blogs listed on

a central site, compared to 152 for Kuwait, and 365 for

Dallas/Fort Worth. These different sizes only loosely correspond

to the populations of the geographical areas, which are a bit under

3 million for both UAE and Kuwait, and over 5 million for DFW.

We use network analysis to determine to what extent each set of

blogs actually forms a community by engaging in reciprocal,

group interaction. But first we examine the different forms of

interaction that can take place.

3.1 Blog ties: blogrolls, citations, and

comments

Social relationships can be expressed online as different forms of

blog ties:

Blogroll links are usually located in the blog‟s sidebar and point

to other blogs that the author may read or simply want to always

include on her main page.

Citation links are made by bloggers within their own posts and

can reference an entire blog or just a particular post on that blog.

By their nature, they occur at a fixed time point, but may be

repeated. Repeated citations can serve as a weight for the tie –

with more frequent citations indicating a greater interest of one

blog for another.

Comment links are not necessarily hyperlinks per se, but an

interaction that occurs when one person, possibly a blogger, adds

a comment to another blogger‟s post.

For both blogrolls and citations, the communication is indirect. It

occurs on the blog with the blogroll or citing blog post, but may

be noticed by the blog being referenced through blog search

engines, server logs, or through TrackBacks. Trackbacks allow the

citing blog to notify the blog receiving the citation that their post

has been discussed [4]. The receiving blog will typically display

the TrackBack, along with summary text of the citing post.

Readers are then able to follow conversations across several blogs

by traversing TrackBacks.

Most of the blog research to date has focused on

blogrolls and citation links [5, 6, 13, 16]. We find, however, that

much of the interesting interaction occurs in comments left by

bloggers directly on a post of another blog. This kind of

communication is more interactive and conversational, and we

observe that bloggers receiving many comments will comment on

their own post in reply to others‟ comments.

3.1.1. Data collection

For all three communities, we gathered the blogroll links by hand

at a single time point. For better coverage, post citations were

collected using two search engines, BlogPulse [3] and Technorati

[8], and the data spanned April 2005 to March 2006 for

Technorati and November 2005 to April 2006 for BlogPulse.

Comments were gathered manually over a two week period just

for the Kuwait blog community.

3.1.2. Link type overlap

Although one might expect that bloggers cite and leave comments

on the blogs that are in their blogrolls, we found that overlap

between the different kinds of ties, while significant, is not

complete. As shown in Figure 1, a majority of both comment ties

and citation links are not present in the blogroll network.

Fig. 1: Venn diagram illustrating the overlap in different types of

blog ties (comments, blogrolls, and citations) for Kuwait Blogs

3.2 Density and centralization

The first measure of community we consider is the density of links

between blogs within that community. The greater blogosphere is

vast, and the chance of a link falling randomly within one of these

small communities is negligible. We find, however, that blogs link

on average to one or more other blogs within the community, with

the Kuwait network being most dense, and the DFW network

most sparse (see Table 1). Overall, blogroll links are more

numerous than post citations.

The communities differ not only in the density of links,

but also in the distribution of those links. Centralization measures

the equality of allocation of links. In all communities, there is

greater centralization of outdegree – meaning that a few blogs

have very long blogrolls and/or cite other blogs often, while many

list few or no other community blogs in their blogrolls.

Kuwait

UAE

DFW

citation

2.08

1.37

0.37

blogroll links

32%

43%

27%

comments

43%

N/A

Table 2: Percentage of links that are reciprocated

In all three communities a greater fraction of blogroll links are

reciprocated than are post citations, possibly because blogroll

links are more numerous in our data set and because bloggers

sometimes reciprocate blogroll links merely as a courtesy.

Furthermore, reciprocal blogroll links indicate possibly only a

mutual awareness, whereas reciprocal post citations imply a

greater level of interaction: both blogs actively discussing or

linking to one another in their posts rather than one blog simply

finding another‟s post interesting enough to cite. Finally, it is

interesting to observe that for the Kuwait blogs, it is the

comments that are most often reciprocated, making commenting

the most conversational and mutual activity in that community.

(a)

(b)

(c)

Fig. 2: Within-community blogroll and post citation links for (a)

DFW, (b) UAE, and (c) Kuwait. Nodes are colored by outdegree:

red – high, blue – low, and sized by their indegree

3.4 Community structure

Often times communities themselves contain subcommunities.

Modularity measures how pronounced this subcommunity

structure is . We use a fast community finding algorithm [10], that

subdivides the nodes into groups in order to maximize the

proportion of edges within groups compared to a random

subdivision. A modularity of 0 means that there is no natural way

to subdivide the network into groups, and a high modularity

means that one can easily subdivide the network (maximum

modularity is 1). As is shown in Table 3, for all three blog

networks, we find relatively high modularity, but it is highest for

DFW, which is the sparsest and most easily broken up network. In

contrast, Kuwait and UAE, while displaying a degree of local

interaction between subgroups of blogs, have a tighter cohesion

overall.

Kuwait

UAE

DFW

maximum modularity

0.24

0.22

0.53

number of communities at

maximum modularity

Table 3: Modularity

3.5 Community boundaries

Specific blogs were included in this study because they were

listed on a central webpage for one of the three communities.

There is a question of how self-contained those communities are:

how much interaction there is across the community boundaries

and whether popular Kuwait, UAE, and DFW blogs were omitted

from the sites. To answer this question we look at the relative

fraction of internal and external interaction and the characteristics

of the most cited blogs outside the community.

Overall, we see a country-level affinity of the blogs. The

5 most blogrolled blogs for all three communities are blogs from

the respective countries. But for the DFW blogs, all (dooce.com,

michellemalkin.com, powerlineblog.com,

captainsquartersblog.com) but the last of the top 5 blogs are A-

list blogs in the United States that are outside of Dallas/Fort

Worth . DFW blogs also have the highest percentage of blogroll

links to blogs outside of their community (91%), while Kuwait

has the lowest (53%). These community statistics are reflected in

Figure 3, showing blogroll networks including external blogs

linked to by blogs from within the community.

The same trend is valid for citations received by the

bloggers from other blog posts. As is shown in Table 4, an

overwhelming majority of citations in Kuwait originate from

within the community (79%), which is not the case for UAE and

DFW. Finally, nearly half of the comments posted on Kuwait

Blogs are made by the Kuwait bloggers themselves.

Kuwait

UAE

DFW

internal post citations

received

79%

24%

16%

internal blogroll links given

47%

22%

non-anonymous comments

received from bloggers

within community

42%

N/A

Table 4: Porosity of community boundaries

Porous community boundaries aside, the high concentration of

links within communities and their significant reciprocity, as well

as cohesion in the overall link structures, all indicate that these

groups of blogs do indeed interact as communities. The Kuwait

Blogs community emerges as the most cohesive according to most

network measures, having the greatest number and most evenly

distributed within-community links per blog, having a majority of

citations fall within the community, and not showing much

subcommunity structure.

4. Online and offline relationships

Having shown that there is substantial community interaction

within each group of blogs, we were further interested in how

these interactions impacted people‟s relationships online and in

real life. Do blogs help facilitate new relationship formation or do

they help maintain relationships that already exist in real life? To

answer this question, we surveyed the three communities, asking

bloggers about their motivations to keep a blog, their commenting

behaviors, their relationship with those who leave comments on

their blog, their relationship to bloggers listed on their blogroll,

and their basic demographic information.

4.1 Survey procedures

The majority of bloggers were contacted regarding the online

survey via email: 135 in Kuwait, 56 in the United Arab Emirates,

and 288 in the Dallas/Fort Worth area, with a reminder email sent

to non-responders after 5 days. Bloggers who did not list their

email addresses on their blogs were notified of the survey by

leaving one comment on their individual blogs. In addition, the

Kuwait Blogs and UAE Blogs communities encouraged

participation by blogging about the survey.

4.2 Survey participants

The survey was completed by 85 bloggers from the Kuwait

community, 38 bloggers from the UAE, and 67 bloggers in DFW,

yielding survey response rates of 63%, 68%, and 23% for each

community respectively. The demographics of the communities

leaned toward the young and highly educated. 68%, 66%, and

85% of the bloggers in DFW, Kuwait, and UAE, respectively,

held undergraduate degrees or higher. Kuwait had a slightly

lower number of masters and advanced degrees due to their

younger demographic: 45% of respondents were in the 18-24 age

group, compared to 21% in UAE and just 8% in DFW.

Interestingly, the residence and citizenship of each community

varied in their uniformity. 98% of Dallas/Ft. Worth bloggers were

living in the United States, 95% were US citizens, and 74%

identified themselves as either white or Caucasian. In contrast,

only 73% of the Kuwait bloggers resided in Kuwait, with a full

22% being Kuwaiti citizens but residing in the United States at

least part time. Finally, 82% of UAE bloggers resided in the

United Arab Emirates, but fully 84% of them were non-nationals.

This is even in excess of the overall UAE demographics where

73% of adults are non-nationals [9]. Based on the survey results,

the three communities are alike in some regards, namely their high

level of education, but different in how diverse their nationalities

and geographical locations are within the communities.

(a)

(b)

(c)

Fig. 3: Blogroll and citation links for (a) DFW, (b) UAE, (c)

Kuwait. Nodes are colored red if they are in the community and

are sized by indegree

4.3 Motivation behind blogging

The first survey question regarding blogging behavior asked why

the respondent had started to blog, with the respondent being able

to select all applicable reasons. One reason „finding new friends‟

corresponds to bloggers‟ desire to expand their social networks,

and another „sharing news with friends and family‟ corresponds to

a desire to enrich and maintain existing offline relationships.

Unsurprisingly, the most popular choice across communities

actually had to do with neither – it was the simple desire to

express oneself through blogging.

Figure 4 shows several interesting and significant

differences; 26% of Kuwait bloggers were motivated by finding

new friends, while 12% of UAE and only 3% of DFW bloggers

listed this as a reason (p < 0.001, Fisher‟s exact test). Interestingly

enough, a respondent who did not select finding new friends as a

motivation for blogging later on in the survey reported having met

her spouse through blogging. This would seem to indicate that

new relationships develop even when people do not set out to

create them. While DFW bloggers may have been less motivated

to find new friends, they were twice as likely to be interested in

maintaining existing relationships with friends and family through

blogging (46%), than either the Kuwait (26%) or UAE bloggers

(23%) (p < 0.05). One blogger from Dallas/Fort Worth shared her

enthusiasm for keeping in touch through blogs:

I wish everybody would blog. It's such an easy way of

knowing what's up in someone's life and what thoughts

are on their mind, important or not. People often think,

'Oh, nobody'd want to read about /my/ boring life,' but

really, sometimes just seeing the world from someone

else's point of view can be fascinating.

Even though many bloggers started blogging to express

themselves, they have certainly become aware of blogs‟ social

nature, as we will see in the next section.

DFW Kuwait UAE

percentage

0.0 0.4 0.8 1.2

expression

online journal

inspired by friend's blog

find new friends

share news w/ friends & family

Fig. 4: Main motivations for blogging

4.4 Intersection of blogging and offline

relationships

Since at least some of the bloggers are motivated by a desire to

share news with friends and family, we were also interested in

quantifying the intersection of bloggers‟ blogging and offline

lives. We did so by focusing on the interactive medium of

comments, which were enabled by nearly all bloggers, and by

asking about the relative proportion of comments the bloggers

receive from people they know offline. Across communities, a

majority of survey respondents (79% of Kuwait bloggers, 81% of

UAE bloggers, and 66% of DFW bloggers) reported that few or

none of the comments they receive are left by individuals whom

they know offline. Moreover, bloggers were also asked about the

comments that they leave on others‟ blogs. 94% of UAE bloggers,

74% of Kuwait bloggers, and 65% of DFW bloggers reported that

few or none of the comments that they write are on the blogs of

individuals whom they know offline. For all three communities,

bloggers are interacting with new people whom they do not know

in real life.

4.5 Using blogs to sustain real-life

relationships with non-bloggers

As small as the overlap is between commenting interaction and

offline interaction, it is even smaller if the offline relationship is

with a non blogger. 99% of Kuwait bloggers, 94% of

UAE bloggers, and 79% of DFW bloggers reported that few or

none of the comments they received were made by people who do

not blog but whom they know offline. It appears that blogs do not

help individuals maintain their real life relationships to non-

bloggers. This finding may not necessarily signify a weakness of

blogging as a communication medium. It may be merely a

function of blogging being a fairly new technology, whereby a

minority of one‟s real life social network actually blogs.

Moreover, there is a possibility that non-blogging real life friends

and contacts do read blogs but do not leave comments.

Furthermore, in the case of Kuwait and UAE bloggers, many blog

anonymously by using a pseudonym, and so are potentially able to

keep their real-world and blogging interactions separate. This also

correlates with our earlier mentioned finding that UAE and

Kuwait bloggers were less interested in blogging to share news

with friends and family.

4.6 Using blogs to maintain and form

relationships

Along with blogging‟s role in maintaining existing offline

relationships, we were interested in its ability to facilitate new

relationship formation. When asked how many of the bloggers on

their blogrolls they had met in person, bloggers in Kuwait and

DFW cited a median of 5 others, while bloggers in the UAE cited

a median of 2 Here we use the median or the middle value rather

than the mean because the distribution is highly skewed. Bloggers

in all three communities had most often reported meeting just 1 or

2 others in person, while some responded that they had met

dozens. These results signal that bloggers do meet each other

offline but they appear to be reserved in doing so. Nonetheless,

bloggers‟ hesitancy to meet bloggers listed on their blogrolls may

be reflective of the casualness of blogroll links.

Bloggers do appear to be more willing to communicate

with other bloggers listed on their blogrolls through email (citing

a median of 5 bloggers in Kuwait, 10 in UAE and 12 bloggers in

DFW), but less likely to communicate through the telephone or

instant messaging (for telephone conversations, citing a median of

3 bloggers in DFW and 2 bloggers in Kuwait and UAE; for

instant messaging, citing a median of 6 bloggers in Kuwait, 2.5

bloggers in UAE, and 2 bloggers in DFW).

Finally, we wanted to know not just whether a blogging

relationship coincided with other forms of communication, but

whether blogging was the cause for the relationship to form in the

first place. When asked to estimate the number of bloggers listed

on their blogrolls whom they initially met through blogging but

whom they now communicate with in person, by phone, email, or

instant messaging, the Kuwait bloggers listed a median of 5, the

UAE bloggers listed a median of 4 other bloggers (approximately

20% of their blogroll), while the DFW bloggers listed a median of

just 3 other bloggers, although two DFW bloggers mentioned

having met upwards of 100 people through blogging.

Along with the quantitative evidence, there is

qualitative support that blogging does enable new relationship

formation. In this regard, one Kuwait Blogs survey respondent

stated:

Most of the Kuwaiti bloggers know one another, either

directly (friends/relatives) or indirectly (friends of

friends, friend's relatives, etc.). If they don't know one

another, then they don't remain strangers for long. […]

I know of several people who used their blogs to make

new friends in Kuwait.

A survey respondent in the Dallas/Fort Worth community shared

a similar experience:

The DFW Blogs community was an incredible social

network for me. I had recently moved back to the Dallas

area when the group began. Through that group I was

able to meet highly intelligent, talented, motivated, and

creative people. We all had a common interest - blogs -

but we were all so diverse. The group was amazing and

I'm so thankful I was apart of it for so many years.

The above questionnaire revealed that blogging relationships tend

to predominantly form online with few of them being existing

offline ties. At the same time they tend to stay online, usually at

most extending to email communication. However, some new

offline relationships did form – showing that online community

formation can translate to real world connections.

5. Conclusion and future work

In this paper we examined three blog communities in different

geographical locations, both by analyzing the network structure of

their blogrolls, citations, and comments, and by surveying the

bloggers directly. In all three communities, there is strong

evidence that blogs do enable relationship formation, with some

of those new relationships later extending to other communication

media and offline meetings. On the other hand, blogs do not play

a large role in helping bloggers sustain their real life relationships;

nonetheless, this finding may be due to blogging‟s relatively

young age. In general, all three communities show high degrees

of reciprocity and cohesion. But we find that bloggers in DFW

tend to more heavily link to A-list blogs outside their community,

while Kuwait and UAE bloggers link more inwardly. In future

work, we would like to compare the strength of the tie specified

by the survey respondents (friend, acquaintance, etc), with the

frequency and type of blog interaction.

Acknowledgments

This study was conducted while the first author was a master‟s

student at the University of Michigan School of Information. We

would like to thank Kate Williams for insightful discussions, TJ

Giuli for helpful comments and suggestions, and the bloggers who

participated in our surveys. We would also like to thank several

anonymous reviewers for their feedback on an earlier draft.

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