Time preferences indicate how much decision makers value future outcomes relative to more immediate outcomes. They can be quantified as a temporal discount rate (the increase in value necessary to offset a delay). The current research extends previous research by the PI by addressing two related research questions. First, how and why do individual discount rates differ from societal and intergenerational discount rates? Whereas most previous research has concerned time preferences that individuals display for outcomes that occur (usually to themselves) in their own lifetime, many important societal intertemporal choices involve outcomes that occur to future generations (e.g., pollution, global warming). Several theorists have argued that the discount rate applied to intergenerational choices should differ (be lower) than that applied to intragenerational decisions, but little empirical research has explored this distinction. Four experiments test two descriptive theories about how and why inter- and intra- generational discount rates might differ. The second question addressed is: can biases in intertemporal choice and choice under uncertainty be explained by common mechanisms? Although there is a sizeable body of research on intertemporal choice, most decision research continues to address choice under uncertainty. Three experiments extend previous work in drawing parallels between intertemporal choice and choice under uncertainty and test the idea that the same decision processes underlie biases in these two domains. These two research questions provide both a basic and an applied focus. These two foci are related because policy outcomes with very long delays almost invariably involve uncertainty as well as delay.
