Spatial discounting

Seth Baum, William Easterling
Project Complete

Discounting across time is a major area of research and a major factor in public and environmental policy. Our overarching goal is to establish discounting across space as being equally fundamental in research and policy contexts. Our specific objectives are threefold: Objective 1, theory: To develop a theoretical basis for space-time discounting, drawing on the root ideas underlying the concept of discounting. Objective 2, psychology: To understand how humans discount across space and time, drawing on existing and original research using surveys and other methodologies. Objective 3, policy: To assess the importance of space-time discounting for policy analysis, in particular climate change policy analysis, drawing on existing policy analysis procedures and our theoretical and psychological research. Our major goal was to develop a new conceptualization of discounting that integrates spatial as well as temporal discounting. This includes three components: ethical theory, psychology, and climate change case studies.


Major Findings

  • The concept of discounting applies to space just as well as to time. Theory: We find that spatial discounting is theoretically analogous to temporal discounting for each of several core reasons for discounting. Psychology: We find that people discount similarly across space as they do across time, at least for the reason for discounting considered in our survey. Policy: We find that existing policies and recommendations for future policies are both heavily dependent on spatial as well as temporal discounting. There are significant results for each of the three project components:
  • For ethical theory, we find that discounting theory can include space alongside time.
  • For the psychology, we find that people discount across space similarly to how they discount across time.
  • For the climate change case studies, we find that spatial discounting is an important component of real-world decision making and that it behaves differently from temporal discounting.


Broader Impacts

  • This project provides important new insights about environmental decisions as made by both private individuals and public policy makers. Specifically, we have identified space-time discounting as a crucial factor in these decisions.
  • The results can impact decision making by both private individuals and public policy makers. Many decisions, including environmental decisions, are significantly influenced by space-time discounting. As our research continues to be disseminated beyond science and technology, the significance of the research can continue to have an impact on society.
  • The research of this project is being disseminated via academic publications, including Baum’s PhD dissertation and several peer reviewed journal articles. In addition, the research is being disseminated to the public via a short-form online video that dramatizes space-time discounting in a format that can achieve a large audience.


CRED2 Award (2010-2015): Funding was provided under the cooperative agreement NSF SES-0951516 awarded to the Center for Research on Environmental Decisions.