HOLA: Human-like Orthogonal Network Layout

Abstract

Fig. 1: Human, yFiles, and HOLA layouts of SBGN Glycolysis-Glygoneogensis pathway. It is clear that the human and the state-of-the-art layout algorithm from yFiles produce structurally quite different layouts. In this paper we explore the reasons why humans arrange such orthogonal network diagrams differently to standard algorithms and use this to inform the design of a new algorithm, HOLA (output shown right-most), that aims to produce more "human-like" layout.Abstract-Over the last 50 years a wide variety of automatic network layout algorithms have been developed. Some are fast heuristic techniques suitable for networks with hundreds of thousands of nodes while others are multi-stage frameworks for higher-quality layout of smaller networks. However, despite decades of research currently no algorithm produces layout of comparable quality to that of a human. We give a new "human-centred" methodology for automatic network layout algorithm design that is intended to overcome this deficiency. User studies are first used to identify the aesthetic criteria algorithms should encode, then an algorithm is developed that is informed by these criteria and finally, a follow-up study evaluates the algorithm output. We have used this new methodology to develop an automatic orthogonal network layout method, HOLA, that achieves measurably better (by user study) layout than the best available orthogonal layout algorithm and which produces layouts of comparable quality to those produced by hand.

High-Quality Ultra-Compact Grid Layout of Grouped Networks

“…[27]), compact node-placement is essential. A strong correllation between human preference and layout compactness is also observed in a recent study by Kieffer et al [29]. R2 -Proximity implies connectivity.…”

“…This approach provides a regularity to the layout that leads the eye in a familiar and comfortable way [37]. Recent studies of network layout have shown that grid arrangements are memorable [35], when people arrange small diagrams themselves they prefer to place nodes at grid-points [42] and such placements are also preferred to TSM-based orthogonal layout [29].…”

Evaluation of Visualization by Critiques

“…E.g. sometimes a table is better than a visualization [2], a summary is better than a tag cloud [36], a deterministic graph layout vs. a spring-based layout [37], and so on.…”

A Symmetry Metric for Graphs and Line Diagrams

“…Many believe greater symmetry improves understandability and that, for example, force-directed layout promotes symmetry [1,2]. In the study of Kieffer et al, human subjects showed a preference for graphs with reflectional symmetry [3]. Likewise, Marriot et al confirmed that various layout featuresincluding symmetry -make graphs more memorable [4].…”