[ 5] Rivadeneira, A.
W., D. M. Gruen, M.
J. Muller, and D. R.
Heads in the Clouds:
Studies of Tagclouds.”
In Proceedings of CHI
tive text analysis, suggests that
experts in information design
might want to rethink the purpose and goals of their creations.
In this moment when nonacademic designers are adopting
academic visualization techniques, theorists can return the
favor and take inspiration from
the current burst of creativity in
[ 6] Hearst, Marti A.,
and Daniela Rosner.
“Tag Clouds: Data
Analysis Tool or
Social Signaller?” In
Proceedings of HICSS
The authors would like to thank
Marti Hearst for insightful comments on an early draft of this
article, and Jonathan Grudin for
the invitation to contribute to
the Timelines forum.
July + August 2008
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search for specific items in the
display. Yet another study has
determined that some users are
oblivious to the fact that words
are alphabetically organized [ 6].
So there’s a puzzle: If tag clouds
don’t provide quantifiable benefits and if people are unaware
of how items are organized in
the visualizations, how and why
are tag clouds being used?
Hearst and Rosner suggested
one possible answer when they
noted that tag clouds seem to
serve another purpose, as social
signifiers that imply a friendly
atmosphere and provide a point
of entry into a complex site [ 6].
Web 2.0 sites tend to attract
thousands, sometimes millions, of users who contribute
content—grasping the scale and
diversity of these contributions
is a challenge. Therefore, having tag clouds that summarize
some of this activity in a simple
manner can be a valuable asset
for the community of users. In
a sense, these clouds may act
as individual and group mirrors
which are fun rather than serious and businesslike. Indeed,
this all-word visualization is
a diagram that even a matho-phobe can love.
But what about tag clouds
that appear outside the realm of
social tagging? Our experience
on Many Eyes suggests a few
other uses. In some cases, tag
clouds function as portraits of
individuals rather than groups.
One person uploaded the text
from 20 blogs he read ( 10 from
men, 10 from women) to create
a gallery of verbal snapshots.
Each cloud was accompanied by
commentary on what it revealed
about the blogger’s personality.
While this certainly was a form
of analysis, the engaging nature
of tag clouds made the technique a natural fit.
In other cases, however, tag
clouds seem to be used for more
traditional analytical purposes.
Numerous bloggers have written
about the tag clouds of political
speeches and have painstakingly examined the differences
among politicians. Here users
actively find, analyze, and
communicate patterns in text,
rather than merely obtaining a
glimpse of the “gist” of a piece
of work. Despite the theoretical concerns, tag clouds have
become a tool of choice for
A tag cloud is truly a “
vernacular” technique—one that does
not come from the visualization
community, and that violates
some of the golden rules of traditional visualization design.
Nevertheless, the tag cloud’s
widespread popularity and flexibility—playing a starring role in
situations ranging from psychological experiments to fiction
writing to political analysis—
suggest that it passes the test of
applicability. One might say that
tag clouds work in practice, but
not in theory.
This failure of conventional
wisdom deserves attention
because it points to new possibilities. The increasing demand
for tag clouds indicates that
there is an important class of
data that users want to visualize: unstructured text. In addition, the value users draw from
such visualizations, as social
signalers or as tools for collec-
ABOUT ThE AUThOrS
Fernanda B. Viégas and
Martin Wattenberg are
research scientists at IBM’s
Visual Communication Lab.
Viégas is known for her
pioneering work on depicting chat histories and
email. Wattenberg’s visualizations of the stock market
and baby names are considered Internet classics.
Both Viégas and Wattenberg are also
known for their visualization-based artwork,
which has been exhibited in venues such
as the Museum of Modern Art in New York,
the London Institute of Contemporary Arts,
and the Whitney Museum of American Art.
The two became a team in 2003 when they
decided to visualize Wikipedia, leading to
the “history flow” project that revealed the
self-healing nature of the online encyclopedia. Their current project, Many Eyes,
explores the power of Web-based visualization and the social forms of data analysis it
Many Eyes: http://many-eyes.com