Provenance-Enabled Data Exploration and Visualization

Level

Beginning to advandced.

Presenters

Cláudio Silva, University of Utah
Juliana Freire, University of Utah
Emanuele Santos, University of Utah
Erik Anderson, University of Utah

Abstract

Scientists are now faced with an incredible volume of data to analyze. To explore and understand the data, they need to assemble complex workflows (pipelines) to manipulate the data and create insightful visual representations. Provenance is essential in this process. The provenance of a digital artifact contains information about the process and data used to derive the artifact. This information is essential for preserving the data, for determining the data's quality and authorship, for both reproducing and validating results -- all important elements of the scientific process. Provenance has shown to be particularly useful for enabling comparative visualization and data analysis. This tutorial will inform computational and visualization scientists, users and developers about different approaches to provenance and the trade-offs among them. Using the VisTrails project as a basis, we will cover different approaches to acquiring and reusing provenance, including techniques that attendees can use for provenance-enabling their own tools. The tutorial will also discuss uses of provenance that go beyond the ability to reproduce and share results.

Working Outline

After discussion, it seems that the tutorial is best broken into two distinct pieces: A user-centric portion focused on using VisTrails, and a power-user or developer-centric portion focusing on plug-ins, mashups, etc.

Introduction to Provenance and VisTrails (1h 30m) - Presenter: Claudio/Erik/Juliana/Manu (?)

Brief view of plugins and released features of VisTrails
Define provenance, explain why it is important for data analysis and visualization
Introduce VisTrails, explain the differences and similarities between VisTrails and other vis and scientific workflow systems
- Say it is open source
- Multi-platform: written in Python+QT
- Downloaded 1000's of times
- Shipped with packages: XXXYYYZZZ
- User-contributed packages: XXXXXXX -- you can add your own! (more later)
Explain the version tree and the action-based provenance model
Show features that are enabled by the action-based provenance, and how they can help in the process of analyzing and visualizing data
- Going back and forth on the tree
- Automatic capture of changes
- Compare different workflows and their results
- Exploring parameter spaces
- Querying workflows by example
- Refining workflows by analogy
Discuss how the action-based provenance model can be combined with interactive tools
- Give a brief overview of the plugins
- Show videos for a couple of them and point to the detailed tutorial of how to build a plugin later.

Basic hands-on usage of VisTrails (1h 30m) - Presenter: Manu

Slides: https://vgc.sci.utah.edu/svn/tutorials/Vis2009/slides/basic_handson.pdf

Building Simple Pipelines
- VisTrails Builder overview
- Adding and connecting modules
- Setting parameters
- Setting module labels
- Accessing module documentation
- Using modules for displaying results in the spreadsheet
Using the Spreadsheet
- Spreadsheet overview
- Syncing cells
- Moving cells
- Saving camera
- Using Edit mode functionality
Using PythonSource
- Defining and using input ports and output ports
Connecting to databases
- Defining custom database connections
- Loading a vistrail from the database
- Saving a vistrail to the database
VisTrails as a Server
- Environment Setup
- Running VisTrails in Server Mode
- Showing Examples to illustrate the types of requests that can be done
  - Querying
  - Executing
  - Getting the result images

Advanced hands-on usage of VisTrails (1h 30m) - Presenter: Erik

This will all be in the context of a very specific example - My first thought was to use Gil's data, as it has many very nice features that build a nice story, but problems with releasing data are pushing me towards a CMOP example.
Organizational principles of the History Tree - QBE, Analogies, Parameter Exploration -> New Version
vtkInteractionHandlers - Slicing and dicing data
PythonSource as callback definition - Picking specific elements
The workflow debugger
Transforming VTK pipelines into VisTrails workflows --- modified version of Dave's script to get all VTK example into a .vt, and show how to query/search that.

Developing a plug-in (30-40m) - Presenter: Manu

Plug-in architecture overview
Different implementation strategies
- Attaching the host plugin to the main application
  - Callback mechanism
  - Undo/Redo Stack
- Communication between Host Plugin and Capture API
  - callbacks
  - Sockets
ParaView Plug-in Implementation
- Explaining required changes to the source
- Showing the limitations
- Demo

New Extensions to VisTrails (50-60m) - Presenter: Claudio/Erik/Juliana/Manu

Display Wall
Provenance Rich Publications
Mashups
Repository
Web-based execution (?)

Tutorials/Vis2009

Contents