This document describes a web-based visual analytics environment that allows end users to visually create mashups of multiple coordinated views through direct manipulation rather than programming. It discusses user interface principles, a survey of existing mashup tools, a prototype, and a usability study. The study found the drag-and-drop interaction was intuitive but synchronization between views needed improvement. Overall the environment showed promise for visual analytics by non-experts.

1. A WEB-BASED
ENVIRONMENT FOR VISUAL
CLIENT SIDE MASHUPS
Lars Grammel,
13-Apr-2010 CHISEL Group, University of Victoria

2. Motivation
2
Provide Flexible and Intuitive Visual
Analytics Tools for End User Analysts

3. Two Aspects of Creating Visualizations
3
 Constructing Single Visualizations
 Coordination and Layout of
Multiple Visualizations
Literature Survey End User Development
Tool Survey Mashup Environments
Prototype Development
Preliminary Prototype Usability Evaluation

4. End User Development Principles
4
 Immersion into Task (Flow)
 Invisible tools
 Direct interaction with domain concepts
 Immediate feedback
 Previews
 Incremental and iterative development
 Learning
 Gentle slope of complexity
 Easy recovery from mistakes
 Entice users into learning
 Collaboration
 Different levels of expertise

5. Mashup Environments Survey
5
 Assessed 6 Mashup Environments
 Barriers to View Coordination &
Configuration:
 Programming (visual dataflow,
widget event wiring, DSLs) instead
of direct manipulation
 No direct manipulation layout of
multiple views (except IBM Lotus
Mashups)

6. 6
Prototype Demo

7. Implementation of Principles
7
 Immersion into Task (Flow)
 Invisible tools [no programming, drag and drop interaction]
 Direct interaction with domain concepts [sets, items, dnd]
 Immediate feedback [highlighting, previews, tooltips]
 Previews [drop previews]
 Incremental and iterative development [flexible workflow]
 Learning [low entry barrier]
 Gentle slope of complexity
 Easy recovery from mistakes [undo / redo]
 Entice users into learning [tooltips]
 Collaboration [workspace sharing]
 Different levels of expertise

8. Usability Study
8
Does our interaction approach work in practice? What
usability issues are hampering the interactions?
Laboratory User Study with 8 Participants (& 1 Pilot)
 Video Tutorial
 Spatio-temporal analysis (2 Tasks)
 Earthquakes & Tsunami Warnings
 Concept analysis (4 tasks)
 Biomedical Ontology Data
 Evaluation Questionnaire
 Ratings, Open Questions

9. Reactions
9
“Visually pleasing to the eye. Very intuitive in that for the most
part it made sense what each window did in terms of function.
The possibilities of what one can produce with this easy
interface seem enormous.” P7
“[I liked that] everything is connected and interactive.” P9
“It is hard to understand what some of the function does.” P3

10. Task Completion
10
Spatio-Temporal Tasks Concept Tasks on Biomedical Data
P2 f-ps f-ps f-s f-s a n-a
P3 f-ps f-ps f-s f-s f-ps n-a
P4 f-s f-ps f-s f-s n-a n-a
P5 f-s f-s f-s f-s f-ps n-a
P6 f-ps f-ps f-s f-s f-ps a
P7 f-s f-ps f-s f-ps f-ps f-s
P8 f-ps f-ps f-s f-s f-ps n-a
P9 f-ps f-s f-s f-s f-s f-s
1 2 1 2 3 4
f-s: finished, succeeded f-ps: finished, partially succeeded a: attempted n-a: not attempted

11. Usability/Usefulness of Features
11

12. Multiple Windows
12
“I liked being able to view the
timeline and the map at the
same time when exploring
earthquake data.” P5
“Resizing windows was annoying
especially since there is a lot of
space on the screen that I felt
was not used because the
default window size is small.” P5
63% of the participants resized
and moved windows frequently.

13. Drag and Drop
13
“When dragging it was very
helpful to see where you can
drag the item to (by lighting up
the possible windows).” P2
“The drag and drop […] had what
you needed right there. At first
glance everything seemed
easier, but as you get deeper
into the tasks I got confused on
how things actually worked.” P7

14. Highlighting of Items and Sets
14
“The use of selections and
highlighting in the different
windows is very helpful to
organize what one is
doing.” P2

15. Custom Sets
15
“I liked the fact that I could easily
look for a specific earthquake
set.” P4
“I could not use a lasso function to
quickly highlight multiple items in
any view.” P5

16. Usability Improvement Opportunities
16
 Synchronized Selections
 Filtered Views
 Access to Actions
 “The hardest part of using the tool was that you had to wait for the mouse
over to happen before you could do something.” P4
 88% of the participants tried using right-click.
 Graph View
 50% of the participants clicked on the node menu indicator.
 88% of the participants inadvertently selected nodes.
 100% of the participants had trouble with the graph layout.

17. Contributions
17
 Drop Target Highlighting
 Drop Previews
 View Coordination using Drag and Drop
 Synchronized Selection
 Filtered Views
 Multiple Named Custom Sets combined with Set
Highlighting

18. Future Work
18
 Navigation Coordination
 Add More Visualizations
 Advanced Visualization Configuration
 Synchronous Collaboration
 Other Devices: Large Screen Multitouch & Tablets
 …

19. Thank you!
19
Lars Grammel
CHISEL Group
University of Victoria
Lars.Grammel@gmail.com