The FlowVizMenu and Parallel Scatterplot Matrix:

Hybrid Multidimensional Visualizations for Network Exploration

Christophe Viau, École de technologie supérieure, MontrealMichael J. McGuffin, École de technologie supérieure, MontrealYves Chiricota, Université du Québec à Chicoutimi, ChicoutimiIgor Jurisica, Ontario Cancer Institute, Toronto

Network exploration by graph metrics

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Network exploration by graph metrics

Computed metrics:• Degree

Network exploration by graph metrics

Computed metrics:• Degree• Closeness centrality• Clustering coefficient• K-core decomposition• ...

Network exploration by graph metrics

Computed metrics:• Degree• Closeness centrality• Clustering coefficient• K-core decomposition• ...

Multi-dimensional visualizations

Scatterplot Matrix(SPLOM)

Parallel Coordinates

Related workUsing a Scatterplot Matrix (SPLOM)and Node-Link Diagram to visualize a graph

GraphDice [Bezerianos et al., 2010]

Related workIntegration of scatterplots and parallel coordinates

Steed et al., 2009 Holten and van Wijk, 2010

Yuan et al., 2009

Our proposed interface

Parallel Scatterplot Matrix

Our proposed interface

Parallel Scatterplot Matrix

FlowVizMenu

Our proposed interface

Parallel Scatterplot Matrix

FlowVizMenu

Attribute-Driven Layout

Our proposed interface

A sequence of scatterplots

A sequence of scatterplots

Rotating scatterplots around the y-axis

Rotating scatterplots around the y-axis

Rotating scatterplots around the y-axis

Parallel Scatterplot Matrix (P-SPLOM)

Scatterplot Matrix(SPLOM)

Rotating around x- or y-axes causes a transition from Scatterplot Matrix (SPLOM) to stacked Parallel Coordinates.

Parallel Coordinates

Ordering of axes within P-SPLOM

Problem: traditional SPLOM ordering doesn’t yield useful parallel coordinates.

Repeated axes: useless for parallel coordinates

Axes are repeated in each row and column

Ordering of axes within P-SPLOM

Solution: order the axes according to a Latin square.

Useful parallel coordinates Each row and column contains each axis once.

Scatterplot Staircase (SPLOS)Inspired partly by quilts [Watson et al. 2008]

Sequence of scatterplots:treats one dimension differently.

Scatterplot Staircase (SPLOS): all dimensions treated uniformly; every adjacent pair of plots share an axis.

Parallel coordinates:more difficult to judge correlations than in scatterplots[Li et al., 2010]

FlowVizMenu

• Variant of a FlowMenuwith embedded visualization

• Smoothly animated transitions

• Brushing and linking• More than

two dimensionspossible with PCA

FlowVizMenu

In-out gesture to quicklyselect axes of scatterplot

Attribute-Driven Layout (ADL)

ADL: Layout based ona scatterplot selected in the FlowVizMenu.

The network layoutcan be a mixture of• Attribute-Driven Layout (ADL)• Manual layout• Force-directed layout

Demo

Initial user feedbackFive bioinformaticians used our prototype and gave feedback.

All had experience working with network data.

Results:

Pros:• Exploring along multiple metrics, smooth transitions,

and integration of views were judged useful• All participants stated they would use the interface

if it were made available to them

Cons:• Some pairings of metrics within the scatterplots

may not be useful• Too many hotkeys + button combinations

in the current prototype

Contributions:Three hybrid multidimensional visualization techniques for visualizing networks

Contributions:Three hybrid multidimensional visualization techniques for visualizing networks

• A Parallel Scatterplot Matrix (P-SPLOM) that transitions between a scatterplot matrix and parallel coordinates

Contributions:Three hybrid multidimensional visualization techniques for visualizing networks

• A Parallel Scatterplot Matrix (P-SPLOM) that transitions between a scatterplot matrix and parallel coordinates

Contributions:Three hybrid multidimensional visualization techniques for visualizing networks

• A Parallel Scatterplot Matrix (P-SPLOM) that transitions between a scatterplot matrix and parallel coordinates

• A FlowVizMenu to quickly select the dimensions for an embedded scatterplot

Contributions:Three hybrid multidimensional visualization techniques for visualizing networks

• A Parallel Scatterplot Matrix (P-SPLOM) that transitions between a scatterplot matrix and parallel coordinates

• A FlowVizMenu to quickly select the dimensions for an embedded scatterplot

Contributions:Three hybrid multidimensional visualization techniques for visualizing networks

• A Parallel Scatterplot Matrix (P-SPLOM) that transitions between a scatterplot matrix and parallel coordinates

• A FlowVizMenu to quickly select the dimensions for an embedded scatterplot

• An Attribute-Driven Layout to configure the graph according to a scatterplot of graph metrics

Future directions

• Application to other domains• Evaluation of performance and usability• Exploration of the design space of each visualization

(e.g., on a small screen)

Acknowledgments

We thank our collaborators for their feedback: • SAP Business Objects • Members of Jurisica Lab at OCI• Members of the Multimedia Lab at ETS

This research was funded by an SAP Business ObjectsARC Fellowship, NSERC, and the FQRNT.

Thank you

P-SPLOM: variants

P-SPLOM: Pearson correlation coefficient

P-SPLOM: Latin square

P-SPLOM: another latin square

Scatterplot Staircase

Parallel Scatterplot Matrix (P-SPLOM)

• Rotating around x- or y-axes causes a transition from Scatterplot Matrix (SPLOM) to stacked Parallel Coordinates

Ordering of axes within P-SPLOM

The traditional SPLOM ordering doesn’t produceinteresting parallel coordinates

Repeated axes: useless for parallel coordinates

P-SPLOM ordering

• We explored variants of latin square