Discount rates are often used in cost-benefit analysis. Whenever costs and benefits for a household or individual are spread over time, it is essential that one calculate present-value equivalents in order to undertake meaningful comparisons. In most cases welfare analysts use market rates as the basis for these present-value calculations. Sensitivity analysis often consists of varying the scal...

Decisions with intergenerational consequences may leave future generations worse off (i.e., not be Pareto optimal) if costs and benefits are not discounted correctly. We point out that this happens if the conventional social discount rate is applied to intergenerational costs: with this rate the justification of intergenerational costs (benefits of a project are invested and the proceeds can co...

This paper considers the issue of discounting in relation to the appraisal of very long-term social projects. This is an increasingly important matter given the growing concerns over the environmental and safety impacts of many projects on future generations. Standard discounting practice trivialises the welfare impacts of projected costs and benefits on future populations, so a credible altern...

It is not immediately clear how to discount distant-future events, like climate change, when the distant-future discount rate itself is uncertain. The so-called “WeitzmanGollier puzzle” is the fact that two seemingly symmetric and equally plausible ways of dealing with uncertain future discount rates appear to give diametrically opposed results with the opposite policy implications. We explain ...

Time Discounting and the Body Mass Index In many Western countries, the relative weight of people measured by the Body Mass Index (BMI) has increased substantially in recent years, leading to an increasing incidence of overweight and related health problems. As with many forms of risky behavior, it is plausible that overweight is related to the individual discount rate. Increases in credit card...

Social discounting in economics involves applying a diminishing weight to community-wide benefits or costs into the future. It impacts on public policy decisions involving future positive or negative effects, but there is no consensus on the correct basis for determining the social discount rate. This study presents an evolutionary biological framework for social discounting. How an organism sh...

abstract in this paper, markov chain and dynamic programming were used to represent a suitable pattern for tax relief and tax evasion decrease based on tax earnings in iran from 2005 to 2009. results, by applying this model, showed that tax evasion were 6714 billion rials**. with 4% relief to tax payers and by calculating present value of the received tax, it was reduced to 3108 billion rials. ...