Target Acquisition in Multiscale Electronic Worlds



Abstract

Since the advent of graphical user interfaces, electronic information has grown exponentially,
whereas the size of screen displays has stayed almost the same. Multiscale interfaces were
designed to address this mismatch, allowing users to adjust the scale at which they interact
with information objects. Although the technology has progressed quickly, the theory has
lagged behind. Multiscale interfaces pose a stimulating theoretical challenge, reformulating
the classic target-acquisition problem from the physical world into an infinitely rescalable
electronic world. We address this challenge by extending Fitts’ original pointing paradigm:
we introduce the
scale variable, thus defining a multiscale pointing paradigm. This article
reports on our theoretical and empirical results. We show that target-acquisition performance
in a zooming interface must obey Fitts’ law, and more specifically, that target-acquisition time
must be proportional to the index of difficulty. Moreover, we complement Fitts’ law by
accounting for the effect of view size on pointing performance, showing that performance
bandwidth is proportional to view size, up to a ceiling effect. The first empirical study shows
that Fitts’ law does apply to a zoomable interface for indices of difficulty up to and beyond 30
bits, whereas classical Fitts’ law studies have been confined in the 2-10 bit range. The second
study demonstrates a strong interaction between view size and task difficulty for multiscale
pointing, and shows a surprisingly low ceiling. We conclude with implications of these
findings for the design of multiscale user interfaces.



More intriguing information

1. The fundamental determinants of financial integration in the European Union
2. Conflict and Uncertainty: A Dynamic Approach
3. Draft of paper published in:
4. The problem of anglophone squint
5. Der Einfluß der Direktdemokratie auf die Sozialpolitik
6. The name is absent
7. Job quality and labour market performance
8. What Contribution Can Residential Field Courses Make to the Education of 11-14 Year-olds?
9. Reconsidering the value of pupil attitudes to studying post-16: a caution for Paul Croll
10. The name is absent
11. Does Competition Increase Economic Efficiency in Swedish County Councils?
12. The name is absent
13. The name is absent
14. The name is absent
15. KNOWLEDGE EVOLUTION
16. The name is absent
17. The name is absent
18. School Effectiveness in Developing Countries - A Summary of the Research Evidence
19. PRIORITIES IN THE CHANGING WORLD OF AGRICULTURE
20. Multi-Agent System Interaction in Integrated SCM