The Q-Exponential Decay of Subjective Probability for Future Reward: A Psychophysical Time Approach

This study experimentally examined why subjective probability for delayed reward decays non-exponentially (“hyperbolically”, i.e., q ˂ 1 in the q-exponential discount function) in humans. Our results indicate that nonlinear psychophysical time causes hyperbolic time-decay of subjective probability for delayed reward. Implications for econophysics and neuroeconomics are discussed.