The environmental Kuznets curve: does one size fit all?

This paper uses a new panel data set on state-level sulfur dioxide and nitr ogen oxide emissions from 1929-1994 to test the appropriateness of the 'one size fits all' reduced-form regression approach commonly used in the envir onmental Kuznets curve literature. Empirical results provide initial eviden ce that an inverted-U shape characterizes the relationship between per capi ta emissions and per capita incomes at the state level. Parameter estimates suggest, however, that previous studies, which restrict cross-sections to undergo identical experiences over time, may be presenting statistically bi ased results. (C) 1999 Elsevier Science B.V. All rights reserved.