A task-based evaluation of combined set and network visualization

Abstract

This paper addresses the problem of how best to visualize network data grouped into overlapping sets. We address it by evaluating various existing techniques alongside a new technique. Such data arise in many areas, including social network analysis, gene expression data, and crime analysis. We begin by investigating the strengths and weakness of four existing techniques, namely Bubble Sets, EulerView, KelpFusion, and LineSets, using principles from psychology and known layout guides. Using insights gained, we propose a new technique, SetNet, that may overcome limitations of earlier methods. We conducted a comparative crowdsourced user study to evaluate all five techniques based on tasks that require information from both the network and the sets. We established that EulerView and SetNet, both of which draw the sets first, yield significantly faster user responses than Bubble Sets, KelpFusion and LineSets, all of which draw the network first.

Evaluating the effects of size in linesets

“…Set visualizations typically plot data items that belong to a set within an enclosed shape [2,7,9,11,15,16,19] but others also visualize sets with lines, such as linear diagrams [10,25]. Where previous comparative evaluations of multiple techniques have revealed the relative strengths of certain techniques [18][19][20], exploiting size (and other features) has been largely overlooked, at least from the perspective of empirically evaluating the impact of design choices to 'optimize' any given technique. Such evaluations might reveal new strengths and weaknesses that could improve the way set visualizations are designed.…”

Evaluating Visualizations of Sets and Networks that Use Euler Diagrams and Graphs

“…Such diagrams will lead to incorrect deductions being made about the underlying data. Existing Techniques A range of techniques draw combined Euler diagrams and graphs, including SetNet [16], WebCola [7], Bubble Sets [4], EulerView [19], Vizster [10] and KelpFusion [13]. A comprehensive overview of these and other techniques is available in [1].…”

“…SetNet [16] often produces diagrams with the ineffective property of nonunique labels, as in Fig. 1.…”

“…We selected techniques for our evaluation such that (a) they drew combined Euler diagrams and graphs, (b) the software was freely available, and (c) they could theoretically visualize any finite collection of sets and associated network, even though the implementation may fail. Bubble Sets [4], SetNet [16] and We-bCola [7] were the techniques that met these criteria. All the diagrams used in our study are available at https://github.com/AlmasB/D2020 and are marked to show where property violations occurred.…”

“…See Fig. 1, drawn using SetNet [16], where two curves labelled A represent the same set A. -Connected zones: all of the zones in the diagram are connected components of the plane; a zone which is not connected is called disconnected.…”