Graphics Reference
In-Depth Information
hese types of content require statistical graphics in order to visualize statisti-
cal data. Early in the history of web publication, static (noninteractive) and raster
(nonvector) graphics formats such as JPEG or GIF were used. However, using the
Java mechanism, it became possible to implement interactive and dynamic graphics
on the Web. However, such graphics did not become su
ciently popular. With the
spread of Flash, the interactive features available on the Web became more popular.
Asaresult,thedemandforinteractive anddynamicgraphics usingwebtechnologyis
rising. In Web-based systems, it is sometimes necessary to create graphics according
to user requests. In such cases, it is impossible to create graphs and prepare infor-
mation beforehand. Moreover, a feature to display detailed information according
to user requests is also necessary. herefore, Web-based statistical graphics packages
require interactive features.
XML and Statistical Graphics
18.1.2
HTML can provide functions on webpages by cooperating with other technologies,
such as CGI or JavaScript, by linking to other pages, and by arranging information
well. However, when the information described in HTML is reused, it is di
cult to
automate these tasks, because the accompanying information consists solely of tags
that control the display of information on the webpage. his causes databases on the
Web to become enormous. herefore, the concept of the semantic web (W
C,
)
was devised in order to allow information to be used e
ciently and effectively.
Semantic web uses the metadata that accompanies all web contents to interpret
exchanges between information devices, without mediation by a human operator, by
conveying the meaning (semantics) of the information to the computer. he basic
technologies forrealizing the semantic web are XML and its associated technologies,
which are standardized by the World Wide Web Consortium (W
C,
).
StandardsbasedonXMLhavebeendevelopedforvariouskindsofdatainorderto
realize thesemantic web.StatDataML andDandDhavebeen developedforstatistical
data, and GML has been developed for geographical information data. To realize
statistical graphics in the semantic web framework, XML graphics such as SVG and
X
D are necessary.
XML-Based Vector Graphics Formats
18.2
What is XML?
18.2.1
As we noted above, standards based on XML have been developed for various forms
ofdatainordertocreatethesemanticweb,includingStatDataML(Meyeretal.,
)
and DandD (DandD Project,
) for statistical data and GML (Open Geospatial
Consortium,
) for geographical information data. But what is XML?
