Speed-accuracy tradeoff of aimed movement: A formal information-theoretic transmission scheme (FITTS)

Julien Gori 1, 2 Olivier Rioul 1, 2 Yves Guiard 3, 4
1 COMNUM - Communications Numériques
LTCI - Laboratoire Traitement et Communication de l'Information
3 DIVA - Design, Interaction, Visualization & Applications
LTCI - Laboratoire Traitement et Communication de l'Information
Abstract :

The rationale for Fitts’ law is that pointing tasks have the information-theoretic analogy of sending a signal over a noisy channel, thereby matching Shannon’s capacity formula. Yet, the currently received analysis is incomplete and unsatisfactory: There is no explicit communication model for pointing; there is a confusion between central concepts of capacity (a mathematical limit), throughput (an average performance measure) and bandwidth (a physical quantity); and there is also a confusion between source and channel coding so that Shannon’s Theorem 17 can be misinterpreted. We develop an information-theoretic model for pointing tasks where the index of difficulty ID is the expression of both a source entropy and a zero-error channel capacity. Then, we extend the model to include misses at rate ε and prove that ID should be adjusted to (1 − ε )ID. Finally, we reflect on Shannon’s channel coding theorem and argue that only minimum movement times, not performance averages, should be considered

Complete list of metadatas

https://hal.telecom-paristech.fr/hal-02287935
Contributor : Telecomparis Hal <>
Submitted on : Friday, September 13, 2019 - 5:30:39 PM
Last modification on : Thursday, October 17, 2019 - 12:36:59 PM

Identifiers

  • HAL Id : hal-02287935, version 1

Citation

Julien Gori, Olivier Rioul, Yves Guiard. Speed-accuracy tradeoff of aimed movement: A formal information-theoretic transmission scheme (FITTS). ACM Transactions on Computer-Human Interaction (TOCHI), 2018. ⟨hal-02287935⟩

Share

Metrics

Record views

8