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Updated: May 31, 2026

Measuring the Subjective Value of Risky and Ambiguous Options using Experimental Economics and Functional MRI Methods
Published on: September 19, 2012
Quantification of deviations from rationality with heavy tails in human dynamics
T Maillart1, D Sornette, S Frei
1Department of Management, Technology and Economics, ETH Zurich, Kreuzplatz 5, CH-8032 Zurich, Switzerland. tmaillart@ethz.ch
Human task completion dynamics reveal new patterns beyond simple power laws. Analysis shows exponential and plateau regimes, indicating varied task fulfillment based on user engagement and response.
Area of Science:
- Complex systems
- Network science
- Computational social science
Background:
- Human task dynamics influence technological, economic, and social systems.
- Queueing theory suggests power-law distributions for task waiting times.
- The universality and limits of power-law behavior in task completion are not fully understood.
Purpose of the Study:
- To investigate the regimes of task completion times for internet users.
- To identify deviations from the pure power-law model in real-world data.
- To understand how user behavior and system load affect task fulfillment.
Main Methods:
- Analysis of anonymized World Wide Web data from Google.
- Characterization of task execution times after message reception.
- Identification of different statistical regimes based on user utilization and response strength.
Main Results:
- The pure power-law distribution is not universally applicable to task completion times.
- Identified an exponential regime for tasks performed with minimal delay.
- Observed a crossover to an asymptotic plateau, indicating some tasks are never completed.
Conclusions:
- Task completion dynamics are more complex than previously modeled by simple queueing theory.
- User time utilization and response to stimuli create distinct performance regimes.
- Findings have implications for understanding online system performance and user behavior.
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