When making decisions between different options, we often consider two basic properties of these options, how risky they are and when they will occur. For example, we may choose to gamble or to wait for a larger reward. Decisions under risk refer to decisions among known probabilistic options, inter-temporal decisions refer to choices between options that will be realized at known future timepoints.
Risky and inter-temporal decisions have been captured theoretically primarily by Ecology and Microeconomics but findings from Behavioral Economics, Psychology and Neuroscience often contradicted theoretical predictions. As a consequence, a wealth of more descriptive models has emerged to explain the findings. A subset of these models has stressed the similarities between risky and inter-temporal decisions. In this chapter we review both core theoretical approaches and empirical findings. We discuss possible explanations for discrepancies and identify key behavioral experiments.