1 SIMS 247: Information Visualization and Presentation Marti Hearst Oct 10, 2005

2 Today Another animation example –Fluid documents The third dimension –The information visualizer and follow-ons –Navigating in 3D space –The debate: does 3D help? Cognitive abilities and 3D 3D vs 2D –Alternative: 2.5D sequences (Automatic generation of assembly instructions)

3 Fluid Documents Zellweger, Chang, Mackinlay. Fluid links for informed and incremental hypertext browsing. CHI'99 Extended Abstracts Better document-reading interface Combines –Lightweight animation –Focus + context

4 3D + Animation Pioneered by Card and Robertson –Had state-of-the-art graphics hardware; wanted to see what happens when pushing the boundaries –Motivated by Card & Moran’s theories of cognitive architecture Information Visualizer (PARC) WebBook/Webforager (PARC, 1996) Data Mountain (MS Research, 1998) Task Gallery (MS Research, 2000)

5 Objective: –Decrease the costs for performing information- intensive tasks, or, alternatively, increase the scope of information that can be utilized for the same cost. Method: –Large Workspaces –Make the immediate workspace virtually larger –Real-Time Interaction –Maximize the interaction rates –Visual Abstractions – Speed assimilation and pattern detection 8 Information Workspaces

6 Information Visualizer research.microsoft.com/~ggr/gi97.ppt 17

7 Web Forager 24

8 Data Mountain Robertson, Czerwinski et al, 1998 Follow-on to Information Visualizer Organizing bookmarks using pile metaphor Uses: –Spatial organization –3D view with 2D interaction –Cartoon animation details –Subtle audio cues Debate: –Is this better than 2D?

9 Task Gallery 23 Robertson et al., 2000

10 3D vs. 2D Cockburn & McKenzie ’02 –Results for prior work with 3D systems are primarily negative for viz of things that are not inherently in 3D, but really results are mixed –Compared 2D, 2½D and 3D views of web page thumbnails –Did this for both physical and virtual interfaces –Compared sparse, medium, and dense displays

11 3D vs. 2D: Cockburn & McKenzie ’02

12 3D vs. 2D Cockburn & McKenzie ’02 –Results: Time taken sig. increased through 2D -> 3D interfaces Subjective assessment sig. decreased 2D -> 3D Performance degraded with denser problems 3D virtual interface produced the slowest times People prefered the physical interfaces People were better at using their spatial memory than they expected to be There was a problem with the physical 2½D display

13 Interacting with 3D spaces Path-drawing for 3D walkthrough, Igarashi et al, UIST ’98 Problem: interacting with 3D via 2D screens Solution: be clever about how to convert 2D to 3D based on what the user is likely to intend

14 The Role of Cognitive Abilities Leitheiser & Munro ‘95 –Summarizes the results of earlier psychological research on spatial aptitiude –Also summarizes work on effects of spatial aptitude and UI use –Presents a study comparing a GUI with a command line interface, taking spatial abilities into account

15 The Role of Cognitive Abilities Leitheiser & Munro ’95 Hypotheses: –Users with high spatial ability would benefit more from the GUI than those with low spatial ability (H1) –Users with high verbal ability would perform better on command line interfaces (H2) Tasks: –Obtain system time, list files, look up a file update time, open a subdirectory, move a file, copy a file, etc –Between subjects GUI (Mac) vs. Command line (DOS) Findings: –H1 supported –H2 not supported –Everyone did better on the GUI Low spatial ability users using the GUI required 90% of the time needed for command line interface

16 Infovis Meta-Analysis (Empirical studies of information visualization: a meta-analysis, Chen & Yu IJHCS 53(5),2000) Goal –Find invariant underlying relations suggested collectively by empirical findings from many different studies Procedure –Examine the literature of empirical infoviz studies 35 studies between 1991 and focused on information retrieval tasks But due to wide differences in the conduct of the studies and the reporting of statistics, could use only 6 studies

17 Infovis Meta-Analysis (Empirical studies of information visualization: a meta-analysis, Chen & Yu IJHCS 53(5),2000) Conclusions: –IR Infoviz studies not reported in a standard format –Individual cognitive differences had the largest effect Especially on accuracy Somewhat on efficiency –Holding cognitive abilities constant, users did better with simpler visual-spatial interfaces –The combined effect of visualization is not statistically significant

18 Gender differences and 3D Previous studies often found gender differences in 3D navigation Czerwinski et al. wondered why; saw a hint in one study, did a followup study in detail Idea: change the assumptions –Make screen wider –Gender performance differences disappear –Both improved

19 Slides from Heiser et al. Sequences of Steps vs 3D + Animation Heiser, Phan, Agarwala, Tversky, Hanrahan ‘04 Domain: assembly instructions Identify –How people conceive of 3D assemblies –How people comprehend visual instructions Validate –Build automated instruction design system –Evaluate usability of resulting instructions

20 Slides from Heiser et al. Ensure Visibility of Parts Show parts added in each step Show mode and location of attachment Avoid changing viewpoint Use physically stable orientation

21 Slides from Heiser et al. Structural diagrams Action diagrams Illustrate Assembly Operations Use action diagrams rather than structural Use arrows and guidelines to indicate attachment

22 Slides from Heiser et al. Usability Study 30 Participants Given 1 of 3 instruction sets: hand-drawn, factory, computer Assemble TV stand using instructions

23 Slides from Heiser et al. Instructions Tested Hand-drawn Computer generated Factory

24 Slides from Heiser et al. Results Hand-drawn Factory Computer Time to assemble (min) Errors: Hand-drawn 1.6 Factory 0.6 Computer 0.5 Users rated task as easiest in computer condition

25 Next Time Martin Wattenberg! –SIMS distinguished lecture: 4-5:30pm –Our class too Some of Martin’s Projects: –Map of the Market –Baby names visualizer –Music arcs –History flow –Bioinformatics visualization –Conversation visualization