Harberger (1971) proposes that the consumer surplus should be used to measure the individual utility and the social welfare. "Since Harberger's paper, the limitation and pitfall of consumer's surplus have been demonstrated systematically and definitively by Chipman and Moore among many others"...

The paper provides a rigorous derivation of the "welfare triangle approximation" (WTA), which is at the center of cost benefit analysis. The result is generalized by showing that the WTA is one of two dual expressions, one of which approximates the change in real consumption, the other the...