Paper-based Tagging of Documents - Human-Computer Interaction - page 154

7.2 Tagging by Association: Tag Menu Card

While Digital Paper Bookmarks is a very intuitive interaction technique, it is rather
course-grained since bookmarks apply to entire pages. Moreover, only a restricted
number of bookmarks can be attached to a document without the bookmarks be-
coming confusing. Therefore, we introduce a second interaction strategy for tag-
ging documents. This relies on one or more separate paper cards for defining and
applying keyword-based tags (Fig. 7.6).
Each Tag Menu Card contains several empty areas. At any time the user can
define a new tag by writing one or several freely-chosen keywords in one of these
areas. After a tag is defined, it is applied using any of the following interactions:

• Writing the tag on an association area of a document (as defined in Section 6.2)

and enclosing it with a circle in order to mark it as a tag (Fig. 7.7 a). The tag
is automatically recognized from the set of previously defined tags on the Tag
Menu Card using handwriting recognition.

Writing the tag on an association area and additionally performing the pen ges-
ture for hyperlinks (Section 6.2) to associate it with the corresponding area on
the Tag Menu Card (Fig. 7.7 b). This small additional effort ensures that tagging
is correctly performed, as it does not rely on handwriting recognition. This is im-
portant when no computer is nearby, as most current digital pens cannot provide
instant feedback on success or failure of the recognition.

•

Although the Tag Menu Card has a printed representation, it can be used for tag-
ging both printed and digital documents. The precise scope of the tag within the
document is defined the same way as when creating hyperlinks (see Section 6.2).
Depending on the type of association area where the tag is written on or associated

Fig. 7.6 A Tag Menu Card provides for defining and applying keyword-based tags