The Volcker task force on tax reform, part of the President’s Economic Recovery Advisory Board, faces a daunting task that is made materially more difficult by ex ante constraints placed on its purview and recommendations. Broad-based reform proposals seem to be out of the question, and distributional constraints appear to eliminate many serious ideas. Nevertheless, I believe that significant t...

Casual observation suggests that Internet media firms sometimes allow consumers to pay to remove advertisements from a free advertisement-based product. In this paper I characterize when this business model is optimal and analyze its impact on advertising quantity and the distribution of surplus. The optimality of the business model depends on the relation between product quality, the annoyance...

This note is a review of: A. J. de Jong Smoothness, semi-stability and alterations. Manuscript 1995, 39 pp.: Publications Mathématiques I.H.E.S. 83, 1996, pp. 51-93.

geosmin and mib are the common factors causing odor in the water. water treatment plants usually employ the conventional processes such as aeration, coagulation, flocculation, chlorination or ozonation and adsorption as preventive measures to reduce water odor. but each of these processes alone cannot completely remove the smell. the smell of fish, grass and mud greatly depends on the excessive...

being observed frequently that projects cannot achieve to their plan duration and their budget. utilizing retrospective method is one of the reasons for this problem. in this research two method, earned duration management and risk management, has been used to remove the gap of the plan and the reality; this enable the project to utilize both high accuracy of the first method and prophecy of th...