# A Comparative Evaluation of Animation and Small Multiples for Trend Visualization on Mobile Phones

## TL;DR

This study compares animated and small multiples scatterplots on mobile phones, finding small multiples often enable faster task completion with nuanced accuracy depending on task specifics, informing mobile visualization design.

## Contribution

It provides an empirical evaluation of animated versus small multiples scatterplots on mobile devices, extending prior research to mobile contexts and analyzing task-dependent effectiveness.

## Key findings

- Small multiples lead to faster task completion.
- Animation yields slightly higher confidence.
- Effectiveness varies by task characteristics.

## Abstract

We compare the efficacy of animated and small multiples variants of scatterplots on mobile phones for comparing trends in multivariate datasets. Visualization is increasingly prevalent in mobile applications and mobile-first websites, yet there is little prior visualization research dedicated to small displays. In this paper, we build upon previous experimental research carried out on larger displays that assessed animated and non-animated variants of scatterplots. Incorporating similar experimental stimuli and tasks, we conducted an experiment where 96 crowdworker participants performed nine trend comparison tasks using their mobile phones. We found that those using a small multiples design consistently completed tasks in less time, albeit with slightly less confidence than those using an animated design. The accuracy results were more task-dependent, and we further interpret our results according to the characteristics of the individual tasks, with a specific focus on the trajectories of target and distractor data items in each task. We identify cases that appear to favor either animation or small multiples, providing new questions for further experimental research and implications for visualization design on mobile devices. Lastly, we provide a reflection on our evaluation methodology.