SCIS Event

Dissertation Defense

Supporting Web-based and Crowdsourced Evaluations of Data Visualizations

Date / Time:

Jun. 24, 2016 @ 10:00 am


Florida International University
ECS: 349


Mershack Okoe
Florida International University

Mershack Okoe


User studies play a vital role in data visualization research because they help measure the strengths and weaknesses of different visualization techniques quantitatively. In addition, they provide insight into what makes one technique more effective than another; and they are used to validate research contributions. However conducting user studies is challenging, time consuming, and expensive.

In this dissertation, we leveraged current research opportunities to provide a framework design that reduces the overhead involved in designing and running controlled user studies of data visualizations. Specifically, we explored the design and implementation of an open-source framework and an online service (VisUnit) that allows visualization designers to easily configure user studies for their web-based data visualizations, deploy user studies online, collect user responses, and analyze incoming results automatically. This allows evaluations to be done more easily, cheaply, and frequently to rapidly test hypotheses about visualization designs.

Our contributions are two-fold: first, we contribute a flexible design and implementation that facilitates the creation of a wide range of user studies with limited effort; second, we provide an evaluation of our design by showing that it can be used to easily replicate many previous user studies, and it can be used to support new research.


Mershack Okoe is a PhD candidate in the School of Computing and Information Sciences at Florida International University, working under the supervision of Dr. Radu Jianu. Mershack received a Master of Science degree in Computer Science from the School of Computing and Information Sciences at Florida International University in 2014 and a Master of Science degree in Advanced Computing from the University of Bristol, UK in 2009. Mershack received his Bachelor of Science degree in Computer Science from Kwame Nkrumah University of Science and Technology, Ghana in 2007. Mershack's research interests are in Data Visualization, Visual Analytics, and Human Computer Interaction.