• Design of 2D Fitts' law ex...

*Result*: Design of 2D Fitts' law experiments: An odd thing about targets.

Title:
Design of 2D Fitts' law experiments: An odd thing about targets.
Authors:
Roig-Maimó MF; Department of Mathematics and Computer Science, University of the Balearic Islands, Palma, 07122, Spain. Electronic address: xisca.roig@uib.es., Mas-Sansó R; Department of Mathematics and Computer Science, University of the Balearic Islands, Palma, 07122, Spain. Electronic address: ramon.mas@uib.es., MacKenzie IS; Department of Electrical Engineering and Computer Science, York University, Toronto, M3J 1P3, Canada. Electronic address: mack@yorku.ca.
Source:
Applied ergonomics [Appl Ergon] 2026 Feb; Vol. 131, pp. 104680. Date of Electronic Publication: 2025 Nov 03.
Publication Type:
Journal Article; Review
Language:
English
Journal Info:
Publisher: Butterworth-Heinemann Country of Publication: England NLM ID: 0261412 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1872-9126 (Electronic) Linking ISSN: 00036870 NLM ISO Abbreviation: Appl Ergon Subsets: MEDLINE
Imprint Name(s):
Publication: Oxford : Butterworth-Heinemann
Original Publication: London.
MeSH Terms:
Research Design*/standards , Computer Peripherals*/standards , Task Performance and Analysis* , Psychomotor Performance*, Humans ; Movement
Contributed Indexing:
Keywords: Fitts’ law; ISO 9241-411; Multi-directional pointing task
Entry Date(s):
Date Created: 20251104 Date Completed: 20251120 Latest Revision: 20251212
Update Code:
20260130
DOI:
10.1016/j.apergo.2025.104680
PMID:
41187693
Database:
MEDLINE

*Further Information*

*We explored the ISO 9241-411 multi-directional tapping (2D) test for evaluating computer pointing techniques. Based on Fitts' law, the test evenly distributes targets around a circular layout and requires the same movement distance between targets for all trials in a sequence. We demonstrate that this is only possible when using an odd number of targets. We reviewed 200 research papers using the 2D task and found that about a third of them use an even number of targets, and consequently report incorrect values for throughput, reinforcing the need to advertise this overlooked but relevant issue. Our findings imply that adhering to an odd number of targets and to the correct definition of movement distance ensures methodological consistency, leading to valid throughput values. Consequently, we argue for revisiting and updating the ISO 9241-411 standard to explicitly state that an odd number of targets is required for the 2D task.
(Copyright © 2025 The Authors. Published by Elsevier Ltd.. All rights reserved.)*

*Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.*