Measuring the Effects of Urban Transportation Policies on the Environment A Survey of Models

Air pollution from urban travel is influenced by travel demand-by its distribution among modes, by congestion levels, and by the characteristics of vehicles and fuels. How well do existing models evaluate the effect of different policies, especially on welfare and on air pollution? Polcy Research W cingPaper disseminatethe findings of work in progress and anoouage the exchange of ideas among Bank staffand all othersintcrested in developmcrt±issucs. Thcsepapers, distributedby theResearchAdvisoty Staff,carythenames oftheauthors,reflect orly tbeirviews, and should beused and cited accordingly. Thefindings, intereations, and conclusions aretheauthors'own.TIheyshould not be atuibuted to the Wodd Bank, its Board of Directrs, its managment, or any of its member countries. Pu bl ic Di sc lo su re A ut ho riz ed Pu bl ic Di sc lo su re A ut ho riz ed Pu bl ic Di sc lo su re A ut ho riz ed Pu bl ic Di sc lo su re A ut ho riz e