Research on information visualization has reached the place where a number of successful point designs have been proposed and a number of techniques of been discovered. It is now appropriate to begin to describe and analyze portions of the design space so as to understand the differences among designs and to suggest new possibilities. This paper proposes an organization of the information visualization literature and illustrates it with a series of examples. The result is a framework for designing new visualizations and augmenting existing designs.

Information has become interactive. Information visualization is the design and creation of interactive graphic depictions of information by combining principles in the disciplines of graphic design, cognitive science, and interactive computer graphics. As the volume and complexity of the data increases, users require more powerful visualization tools that allow them to more effectively explore large abstract datasets. This

Calendar applications for small handheld devices are growing in popularity. This led us to develop DateLens, a novel calendar interface for PDAs designed to support complex tasks. It uses a fisheye representation coupled with compact overviews to give the big picture in a small space. The interface also gives users control over the visible time period, as well as supporting integrated search to discover patterns and outliers. Designed with device scalability in mind, DateLens currently runs on desktop computers as well as PDAs. Two user studies have been conducted to examine the viability of DateLens as a replacement for traditional calendar visualizations. In the first study, non-PDA users performed complex tasks significantly faster with DateLens than with the Microsoft Pocket PC 2002 ™ calendar (using a PDA emulator). In addition, they rated DateLens as being easier to use than the default calendar application for a majority of the tasks. In the second study, the participants were expert Pocket PC users and the software was run on their own devices. Again, DateLens performed significantly faster for the complex tasks, and there were satisfaction differences favoring each calendar for different kinds of tasks. From these studies, it is clear that DateLens is superior for more complex tasks such as those associated with longer time periods. For daily event tracking, users familiar with the default Pocket PC calendar strongly preferred its daily view and behaviors. Categories and Subject Descriptors:

FOCUS, the Feature-Oriented Catalog USer interface, is an interactive table viewer for a common kind of table, namely the object-attribute table, also called cases-by-attribute table or relational table. Typical examples of these tables are the Roll Calls in BYTE where the features and test results of a family of hardware or software products are compared. FOCUS supports data exploration by a combination of a focus+context or fisheye technique, a hierarchical outliner for large attribute sets, and a general and easy-to-use dynamic query mechanism where the user simply clicks on desired values found in the table. A PC/Windows implementation of FOCUS is publicly available

In information visualization, as the volume and complexity of the data increases, researchers require more powerful visualization tools that enable them to more effectively explore multidimensional datasets. In this paper, we discuss the general utility of a novel visualization spreadsheet framework. Just as a numerical spreadsheetenables exploration of numbers, a visualization spreadsheet enables exploration of visual forms of information. We show that the spreadsheet approach facilitates certain information visualization tasks that are more difficult using other approaches. Unlike traditional spreadsheets, which store only simple data elements and formulas in each cell, a visualization spreadsheetcell can hold anentire complex data set, selection criteria, viewing specifications, and other information needed for a full-fledged information visualization. Similarly, inter-cell operations are far more complex, stretching beyond simple arithmetic and string operations to encompass a range of domain-specific operators. We have built two prototype systems that illustrate some of these research issues. The underlying approach in our work allows domain experts to define new data types and data operations, and enables visualization experts to incorporate new visualizations, viewing parameters, and view operations. 1

New user interface challenges are arising because people need to explore and perform many diverse tasks involving large quantities of abstract information. Visualizing information is one approach to these challenges. But visualization must involve much more than just enabling people to "see" information. People must also manipulate it to focus on what is relevant and reorganize it to create new information. They must also communicate and share information in collaborative settings and act directly to perform their tasks based on this information. These goals suggest the need for information visualization workspaces with new interaction approaches. We present several systems - Visage, SAGE and SDM - that comprise such a workspace and a suite of user interface techniques for creating and manipulating integrative visualizations. Our work in this area revealed the need for interfaces that enable people to communicate with systems in multiple complementary ways. We discuss four dimensions f...

Information visualization encounters a wide variety of different data domains. The visualization community has developed representation methods and interactive techniques. As a community, we have realized that the requirements in each domain are often dramatically different. In order to easily apply existing methods, researchers have developed a semiology of graphic representations. We have extended this research into a framework that includes operators and interactions in visualization systems, such as a visualization spreadsheet. We discuss properties of this framework and use it to characterize operations spanning a variety of different visualization techniques. The framework developed in this paper enables a new way of exploring and evaluating the design space of visualization operators, and helps end--users in their analysis tasks. Keywords: information visualization, operators, user interactions, view/value, framework, spreadsheet, design, extensibility, visualization systems. 1...

To aid designers of digital library interfaces, we present a framework for the design of information representations in terms of previews and overviews. Previews and overviews are graphic or textual representations of information abstracted from primary information objects. Previews act as surrogates for one or a few objects and overviews represent collections of objects. A design framework is elaborated in terms of the following three dimensions: (1) What information objects are available to users, (2) How information objects are related and displayed, and (3) How users can manipulate information objects. When utilized properly, previews and overviews allow users to rapidly discriminate objects of interest from those not of interest, and to more fully understand the scope and nature of digital libraries. This paper presents a definition of previews and overviews in context, provides design guidelines, and describes four example applications.

This paper describes techniques for maximizing the efficient use of small screen space by combining delayed response with semi-transparency of control objects ("widgets") and on-screen text. Most research on the limitations of small display screens has focused on methods for optimizing concurrent display of text and widgets at the same level of transparency (that is, both are equally opaque). Prior research which proposes that widgets may be made semi-transparent is promising, but it does not, we feel, adequately address problems associated with user interaction with text that is partially obscured by the widgets. In this paper, we will propose that a variable delay in the response of overlapping widgets and text improves the effectiveness of the semi-transparent widget/text model. Our conclusions are based on usability studies of a prototype of an online newspaper that combined transparency and delayed-response techniques. Keywords: PDAs, icons, transparency, usability study

We have designed two interfaces to support one-handed thumb use for PDAs and cell phones. Both use Scalable User Interface (ScUI) techniques to support multiple devices with different resolutions and aspect ratios. The designs use variations of zooming interface techniques to provide multiple views of application data: AppLens uses tabular fisheye to access nine applications, while LaunchTile uses pure zoom to access thirty-six applications. Two sets of thumb gestures represent different philosophies for one-handed interaction. We conducted two studies to evaluate our designs. The first study explored whether users could learn and execute the AppLens gesture set with only minimal training. Participants performed more accurately and efficiently using semantic gestures for directional navigation than abstract gestures for object interaction. A second study gathered user reactions to each interface, as well as comparative preferences. With minimal exposure to each design, most users favored the tabular fisheye interface.