Allan Fong Hanseung Lee Rongjian Lan University of M aryland Department of Computer Science
description
Transcript of Allan Fong Hanseung Lee Rongjian Lan University of M aryland Department of Computer Science
Temporal Search and Replace: A novel tool to simplify event sequences in large complex temporal datasets
Allan FongHanseung LeeRongjian Lan
University of MarylandDepartment of Computer
Science
Outline
Background
Our Contributions
Temporal Search and Replace Features
User Interface & Interaction Description
Demo
Search Algorithm
Conclusions and Future Work
Background Motivation:
Simplify the visualization of large complex temporal datasets
Related works:
Search and replace research for graphics [Kurlander 1992] [Yeh 2006]
Psychology research
Miller’s 7 +/- 2 and chunking [Miller 1956]
Temporal chunking (clustering) [Farrell 2012]
Gestalt perception
(202) 456 - 2121
Our Contributions Goal:
Develop and integrate a Temporal Search and Replace tool into EventFlow
Contributions:
Replace capabilities in EventFlow
Search capability for repeating sequences
Search capability for no ordered sequences
Search capability using wildcard notations
Customers/End Users:
Megan Monroe and Catherine Plaisant (UMD HCIL)
Sheila Weiss (UMD Baltimore)
Temporal Search and Replace FeaturesType Shape & Color Visualization
Point Event Colored Triangle
Interval Event Colored Interval Shape
Any Point Event Black Triangle
Any Interval Event Black Interval Shape
Any Event Black Diamond
Repetition Black Rectangle
No Order Red Oval
≥4 { ,= ,
, ,, }
≥2= {
, …},
• One time stamp (e.g., one day)Journal Published: 5/1/10
• Two time stamps (e.g., start time and an end time)Professor: 9/5/09 - 9/30/11
Visualizing Nested Constraints
• Reverse (BFS) Breadth-First Search is used to plot inner constraint boxes & ovals first
• Dynamic add / remove constraints are easily done using the following property All nodes on the same
level are disjoint setsA parent node contains
the range of all its child nodes
Indices:
Constraints:
Events:
User Interface & Interaction
Demo
Search Algorithm Repetition
• We extend the original EventFlow fixed-length pattern search algorithm(Temporal Pattern Search - TPS) to support flexible pattern searching.
• Search index is repeatedly reset so a pattern can be matched multiple times
No Order
• Instead of permuting the events and do sequential event matching, keep matching greedily until each event in the constraint is matched for once.
Wildcard
• Finding any event after the current time in the record
Embedded Constraints Using tree structure to store the embedded constraints
Using stack to store the active constraints
Stack
Indices:
Constraints:
Events:
Conclusions and Future Work Introduce a novel temporal event search and replace tool
Extend EventFlow’s search algorithm to support repetition, no order and wildcard constraints.
Conduct user study with 9 participants
Future work includes:
Add rules that better suit the purpose of simplification of temporal events.
Polish the user interface to reduce the stress of query formulation.
Pattern-level find and replace.
Acknowledgements Megan Monroe, Catherine Plaisant, and Ben Shneiderman
Sheila Weiss
Kent Norman
And for all the participants of the usability study!
Thank you for your attention!
Question?
Backup Slides
Usability Study 9 participants (5 males, 4 females,
mean age 26.7, std 2.5)
Background review, Training session, Usability testing
Search for event sequence and replace
Search for people who had both book and newspaper publications where order is not important
Search for people who have at least 10 conference publications
Search and replace all publication events
Very noticeable reduction in visual clutter after using Tool
Repetition more intuitive than No Order and Wildcard searches
Recommended ImprovementsRecommendation Level of
ImpactImplementation Difficulty
R1 Set a default replacement glyph for users that they can easily edit High EasyR2 Set default interval glyphs to span the entire search event sequence High EasyR3 Make it easier to select and drag edges of interval markers Medium MediumR4 Reduce space between two event sequence boxes High EasyR5 Add visualization of where replacement events are snapping to in the original
sequence Medium High
R6 Add features to let users search and incrementally replace sequences High HighR7 Combine the two-steps search and replace process into one step Medium EasyR8 Map the flow of user clicks for all tasks to systematically eliminate unnecessary
clicks High High
R9 Activate event constraint windows with a button rather than the click and draft option or make the click and drag response less sensitive
Medium High
R10 Create a generic wildcard Medium HighR11 Include summary of the number of replacements found High MediumR12 Add time constraints for event sequences, such as searching between two time
periods High High
R13 Make interval glyph more representative of intervals, particularly in the overview panel
Low Medium
R14 Include additional ranking features, such as ranking by interval duration or ranking by the number of events in an interval
High High
R15 Automate the alignment of event sequences after a search Low Medium