Discounting is traditionally defined as the process of comparing the values of gains and losses that occur at different times. The gains and losses are often - but not always - expressed in terms of money. For example, which would you value more: $100 today, or $200 in 10 years? How about one cookie now, or two cookies in 10 years? To make these decisions, we discount. Discounting is important not just to our own decisions as individuals, but also to the collective decisions we make for policy and other matters. Discounting is especially important for very long-term issues. This includes many major environmental issues such as climate change. Indeed, many debates about how we should respond to climate change have focused on how we should discount. These debates have been particularly prominent in the aftermath of the Stern Review on the economics of climate change. Contributions to discussions of discounting have come from scholars in many fields, including economics, ethics, psychology, law, and environmental stuides, among others.
My Ph.D. research was on discounting. This research covered several aspects of discounting. Some philosophical research explores what exactly discounting is. Some ethics research critiques certain views on discounting and promotes others. Some psychological research examines how people discount. Finally, some applied research uses discounting to analyze climate change and other topics.
A running theme in my discounting research was the concept of spatial discounting. If temporal discounting is the process of comparing the values of gains and losses that occur at different times, then spatial discounting is the process of comparing the values of gains and losses that occur at different places. My Ph.D. dissertation focuses on spatial discounting, as do several related publications.
My main publications on discounting are Discounting Across Space and Time in Climate Change Assessment, "Space-time discounting in climate change adaptation" and "Description, prescription and the choice of discount rates". There are also discussions of discounting in "Intrinsic ethics regarding integrated assessment models for climate management", "Is humanity doomed? Insights from astrobiology", "Cost-benefit analysis of space exploration: Some ethical considerations", "The 'Hidden' Social Costs of Forestry Offsets", and "Beyond the Ramsey model for climate change assessments".
For those new to discounting, I recommend "Against the social discount rate" (pdf) by Tyler Cowen and Derek Parfit and "Valuing future life and future lives: A framework for understanding discounting" (pdf) by Shane Frederick.
Created 8 Mar 2010 * Updated 20 Jun 2016