People’s desire to be patient or impatient can fluctuate from
moment to moment, yet little is known about the effects of
variability in time preference on intertemporal choice
behavior. We examine this issue through the lens of an
exponential discounting model with noisy discount factors. We
show that such a model can generate decreasing patience over
time, accounting for behavioral patterns typically attributed to
hyperbolic discounting, while also making reasonable
predictions regarding violations of intertemporal dominance.
Additionally, two experiments reveal that many participants do
display noise in their discount factors, and that a noisy discount
factor model outperforms hyperbolic models in terms of
quantitative fit. Ultimately the majority of participants are best
described by some type of exponential discounting model
(with or without noisy discount factors). These results indicate
that it may not be necessary to assume alternate forms of non-
exponential discounting, as long as the discount factors in an
exponential model are permitted to vary at random. These
results also highlight the importance of allowing for different
sources of noise in choice modeling.People’s desire to be patient or impatient can fluctuate from
moment to moment, yet little is known about the effects of
variability in time preference on intertemporal choice
behavior. We examine this issue through the lens of an
exponential discounting model with noisy discount factors. We
show that such a model can generate decreasing patience over
time, accounting for behavioral patterns typically attributed to
hyperbolic discounting, while also making reasonable
predictions regarding violations of intertemporal dominance.
Additionally, two experiments reveal that many participants do
display noise in their discount factors, and that a noisy discount
factor model outperforms hyperbolic models in terms of
quantitative fit. Ultimately the majority of participants are best
described by some type of exponential discounting model
(with or without noisy discount factors). These results indicate
that it may not be necessary to assume alternate forms of non-
exponential discounting, as long as the discount factors in an
exponential model are permitted to vary at random. These
results also highlight the importance of allowing for different
sources of noise in choice modeling.