academic homepage at ETS,
research papers and videos,
google scholar profile,
twitter account,
youtube channel.

Selected research projects:

Multitouch Radial Menu presented at AVI 2016

Financevis.net survey of visualizations of financial data, published 2014. (Follow-up work by Ko et al.)

Generalized Plot Matrix (GPLOM) is a way of visualizing multidimensional multivariate data, published 2013. (Some really nice follow-up work by others: Domino by Gratzl et al., 2014.)

Analysis of the Space-Efficiency of Visualizations of Trees, published 2010. (Related work on tree visualization by others that I really admire: treevis.net and Schulz et al. 2013 (JavaScript demo))

A hotbox (popup widget) for interacting with a graph visualization; won an Honorable Mention at IEEE InfoVis 2009

NodeTrix, a hybrid graph visualization that combines node-link diagrams with adjacency matrices, published 2007. (Very relevant follow-up work on hybrid visualizations by others: Javed and Elmqvist, 2012)

Elastic Hierarchies, a hybrid tree visualization that combines node-link diagrams with treemaps, published 2005

Visualizing genealogies, published 2005. (Really nice follow-up work by others: GeneaQuilts)

Visualizing volumetric data, published 2003. (If you're interested in more recent related work, especially with nicer rendering, check out work by Carlos Correa and the book Real-Time Volume Graphics by Engel et al.)

For profs and instructors:

Course slides on HCI topics that I've translated to English
Slides about recent trends in user interfaces (updated 2016)
Slides showing examples of user-centered design (2015)
Slides about the use of sketching to generate design ideas (updated 2016) (adapted from slides by the authors of this book by Greenberg, Carpendale, Marquardt, Buxton)
Slides about prototyping user interfaces (updated 2016)
Slides about JavaScript programming (updated 2016)
Examples of JavaScript that draw on a canvas, retrieve mouse events, retrieve multitouch input events, and draw a 3D mesh with no special libraries
Examples of JavaScript using D3 to generate a barchart and scatterplot, demonstrating 3 ways to read in a CSV data file
Slides on information visualization (updated 2016)
A few figures illustrating concepts in visualization (updated 2012)
Slides about Fitts' law (updated 2016)
Slides about gesture recognition algorithms (2016)

For programmers:

A tutorial on algorithms for visualizing graphs / networks. Check out the follow-up notes written after the article was published.

JWinPointer.jar is a Java library for multitouch and stylus pen input events on Microsoft Windows 10

Notes for programmers on reading raw input events over USB from a Wacom Cintiq 24HD touch on Linux using C++ or Java, or on MS Windows 7 using Java (updated 2014).

For anyone interested in science:

Turning a sphere inside out

The most interesting videos I've seen on youtube

An incomplete list of the most interesting things I've learned in my life