Energy consumption, income, and carbon emissions in the United States
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- de Bruyn, S. M. & van den Bergh, J. C. J. M. & Opschoor, J. B., 1998. "Economic growth and emissions: reconsidering the empirical basis of environmental Kuznets curves," Ecological Economics, Elsevier, vol. 25(2), pages 161-175, May.
- Stern, David I., 2004. "The Rise and Fall of the Environmental Kuznets Curve," World Development, Elsevier, vol. 32(8), pages 1419-1439, August.
- Suri, Vivek & Chapman, Duane, 1998. "Economic growth, trade and energy: implications for the environmental Kuznets curve," Ecological Economics, Elsevier, vol. 25(2), pages 195-208, May.
- Kwiatkowski, Denis & Phillips, Peter C. B. & Schmidt, Peter & Shin, Yongcheol, 1992.
"Testing the null hypothesis of stationarity against the alternative of a unit root : How sure are we that economic time series have a unit root?,"
Journal of Econometrics, Elsevier, vol. 54(1-3), pages 159-178.
- Kwiatkowski, D. & Phillips, P.C.B. & Schmidt, P., 1990. "Testing the Null Hypothesis of Stationarity Against the Alternative of Unit Root : How Sure are we that Economic Time Series have a Unit Root?," Papers 8905, Michigan State - Econometrics and Economic Theory.
- Denis Kwiatkowski & Peter C.B. Phillips & Peter Schmidt, 1991. "Testing the Null Hypothesis of Stationarity Against the Alternative of a Unit Root: How Sure Are We That Economic Time Series Have a Unit Root?," Cowles Foundation Discussion Papers 979, Cowles Foundation for Research in Economics, Yale University.
- Munasinghe, Mohan, 1999. "Is environmental degradation an inevitable consequence of economic growth: tunneling through the environmental Kuznets curve," Ecological Economics, Elsevier, vol. 29(1), pages 89-109, April.
- Selden Thomas M. & Song Daqing, 1994. "Environmental Quality and Development: Is There a Kuznets Curve for Air Pollution Emissions?," Journal of Environmental Economics and Management, Elsevier, vol. 27(2), pages 147-162, September.
- Kaufmann, Robert K. & Davidsdottir, Brynhildur & Garnham, Sophie & Pauly, Peter, 1998. "The determinants of atmospheric SO2 concentrations: reconsidering the environmental Kuznets curve," Ecological Economics, Elsevier, vol. 25(2), pages 209-220, May.
- Theodore Panayotou, 2000. "Economic Growth and the Environment," CID Working Papers 56A, Center for International Development at Harvard University.
- Zapata, Hector O & Rambaldi, Alicia N, 1997.
"Monte Carlo Evidence on Cointegration and Causation,"
Oxford Bulletin of Economics and Statistics, Department of Economics, University of Oxford, vol. 59(2), pages 285-298, May.
- Zapata, Hector O. & Rambaldi, Alicia N., 1996. "Monte Carlo Evidence On Cointegration And Causation," Staff Papers 31690, Louisiana State University, Department of Agricultural Economics and Agribusiness.
- Holtz-Eakin, Douglas & Selden, Thomas M., 1995.
"Stoking the fires? CO2 emissions and economic growth,"
Journal of Public Economics, Elsevier, vol. 57(1), pages 85-101, May.
- Douglas Holtz-Eakin & Thomas M. Selden, 1992. "Stoking the Fires? Co2 Emissions and Economic Growth," NBER Working Papers 4248, National Bureau of Economic Research, Inc.
- Gene M. Grossman & Alan B. Krueger, 1995.
"Economic Growth and the Environment,"
The Quarterly Journal of Economics, President and Fellows of Harvard College, vol. 110(2), pages 353-377.
- Gene M. Grossman & Alan B. Krueger, 1994. "Economic Growth and the Environment," NBER Working Papers 4634, National Bureau of Economic Research, Inc.
- Rothman, Dale S., 1998. "Environmental Kuznets curves--real progress or passing the buck?: A case for consumption-based approaches," Ecological Economics, Elsevier, vol. 25(2), pages 177-194, May.
- Cleveland, Cutler J. & Kaufmann, Robert K. & Stern, David I., 2000. "Aggregation and the role of energy in the economy," Ecological Economics, Elsevier, vol. 32(2), pages 301-317, February.
- Jha, Raghbendra & Murthy, K. V. Bhanu, 2003.
"An inverse global environmental Kuznets curve,"
Journal of Comparative Economics, Elsevier, vol. 31(2), pages 352-368, June.
- Jha, Raghbendra & Bhanu Murthy, KV, 2001. "An Inverse Global Environmental Kuznets Curve," Departmental Working Papers 2001-02, The Australian National University, Arndt-Corden Department of Economics.
- Agras, Jean & Chapman, Duane, 1999. "A dynamic approach to the Environmental Kuznets Curve hypothesis," Ecological Economics, Elsevier, vol. 28(2), pages 267-277, February.
- Theodore Panayotou, 2000. "Economic Growth and the Environment," CID Working Papers 56, Center for International Development at Harvard University.
- Brian R. Copeland & M. Scott Taylor, 2004.
"Trade, Growth, and the Environment,"
Journal of Economic Literature, American Economic Association, vol. 42(1), pages 7-71, March.
- Copeland,B.R. & Scott Taylor,M., 2003. "Trade, growth and the environment," Working papers 10, Wisconsin Madison - Social Systems.
- Brian R. Copeland & M. Scott Taylor, 2003. "Trade, Growth and the Environment," NBER Working Papers 9823, National Bureau of Economic Research, Inc.
- Elliott, Graham & Rothenberg, Thomas J & Stock, James H, 1996.
"Efficient Tests for an Autoregressive Unit Root,"
Econometrica, Econometric Society, vol. 64(4), pages 813-836, July.
- Graham Elliott & Thomas J. Rothenberg & James H. Stock, 1992. "Efficient Tests for an Autoregressive Unit Root," NBER Technical Working Papers 0130, National Bureau of Economic Research, Inc.
- Tom Doan, "undated". "GLSDETREND: RATS procedure to perform local to unity GLS detrending," Statistical Software Components RTS00077, Boston College Department of Economics.
- Tom Doan, "undated". "ERSTEST: RATS procedure to perform Elliott-Rothenberg-Stock unit root tests," Statistical Software Components RTS00066, Boston College Department of Economics.
- Lantz, V. & Feng, Q., 2006. "Assessing income, population, and technology impacts on CO2 emissions in Canada: Where's the EKC?," Ecological Economics, Elsevier, vol. 57(2), pages 229-238, May.
- Hettige, Hemamala & Mani, Muthukumara & Wheeler, David, 2000. "Industrial pollution in economic development: the environmental Kuznets curve revisited," Journal of Development Economics, Elsevier, vol. 62(2), pages 445-476, August.
- Stern, David I., 2002. "Explaining changes in global sulfur emissions: an econometric decomposition approach," Ecological Economics, Elsevier, vol. 42(1-2), pages 201-220, August.
- Heil, Mark T. & Selden, Thomas M., 2001. "Carbon emissions and economic development: future trajectories based on historical experience," Environment and Development Economics, Cambridge University Press, vol. 6(1), pages 63-83, February.
- Toda, Hiro Y. & Yamamoto, Taku, 1995. "Statistical inference in vector autoregressions with possibly integrated processes," Journal of Econometrics, Elsevier, vol. 66(1-2), pages 225-250.
- Roberts, J. Timmons & Grimes, Peter E., 1997. "Carbon intensity and economic development 1962-1991: A brief exploration of the environmental Kuznets curve," World Development, Elsevier, vol. 25(2), pages 191-198, February.
- Soytas, Ugur & Sari, Ramazan, 2003. "Energy consumption and GDP: causality relationship in G-7 countries and emerging markets," Energy Economics, Elsevier, vol. 25(1), pages 33-37, January.
- Dinda, Soumyananda & Coondoo, Dipankor, 2006.
"Income and emission: A panel data-based cointegration analysis,"
Ecological Economics, Elsevier, vol. 57(2), pages 167-181, May.
- Dinda, Soumyananda & Coondoo, Dipankor, 2001. "Income and Emission: A Panel Data based Cointegration Analysis," MPRA Paper 50591, University Library of Munich, Germany, revised 10 Mar 2003.
- Dinda, Soumyananda & Coondoo, Dipankor, 2003. "Income and Emission: A Panel Data based Cointegration Analysis," Conference papers 331072, Purdue University, Center for Global Trade Analysis, Global Trade Analysis Project.
- William T. Harbaugh & Arik Levinson & David Molloy Wilson, 2002.
"Reexamining The Empirical Evidence For An Environmental Kuznets Curve,"
The Review of Economics and Statistics, MIT Press, vol. 84(3), pages 541-551, August.
- William Harbaugh & Arik Levinson & David Wilson, 2000. "Reexamining the Empirical Evidence for an Environmental Kuznets Curve," NBER Working Papers 7711, National Bureau of Economic Research, Inc.
- William Harbaugh & Arik Levinson & David Wilson, 2000. "Reexamining the Empirical Evidence for an Environmental Kuznets Curve," Working Papers gueconwpa~00-00-07, Georgetown University, Department of Economics.
- Sims, Christopher A & Stock, James H & Watson, Mark W, 1990. "Inference in Linear Time Series Models with Some Unit Roots," Econometrica, Econometric Society, vol. 58(1), pages 113-144, January.
- Unruh, G. C. & Moomaw, W. R., 1998. "An alternative analysis of apparent EKC-type transitions," Ecological Economics, Elsevier, vol. 25(2), pages 221-229, May.
- Koop, Gary & Pesaran, M. Hashem & Potter, Simon M., 1996. "Impulse response analysis in nonlinear multivariate models," Journal of Econometrics, Elsevier, vol. 74(1), pages 119-147, September.
- repec:bla:ausecp:v:41:y:2002:i:2:p:239-54 is not listed on IDEAS
- Serena Ng & Pierre Perron, 2001.
"LAG Length Selection and the Construction of Unit Root Tests with Good Size and Power,"
Econometrica, Econometric Society, vol. 69(6), pages 1519-1554, November.
- Serena Ng & Pierre Perron, 1997. "Lag Length Selection and the Construction of Unit Root Tests with Good Size and Power," Boston College Working Papers in Economics 369, Boston College Department of Economics, revised 01 Sep 2000.
- Liaskas, K. & Mavrotas, G. & Mandaraka, M. & Diakoulaki, D., 2000. "Decomposition of industrial CO2 emissions:: The case of European Union," Energy Economics, Elsevier, vol. 22(4), pages 383-394, August.
- Khanna, Neha, 2002. "The income elasticity of non-point source air pollutants: revisiting the environmental Kuznets curve," Economics Letters, Elsevier, vol. 77(3), pages 387-392, November.
- Andreoni, James & Levinson, Arik, 2001.
"The simple analytics of the environmental Kuznets curve,"
Journal of Public Economics, Elsevier, vol. 80(2), pages 269-286, May.
- James Andreoni & Arik Levinson, 1998. "The Simple Analytics of the Environmental Kuznets Curve," NBER Working Papers 6739, National Bureau of Economic Research, Inc.
- Bradford David F. & Fender Rebecca A & Shore Stephen H. & Wagner Martin, 2005.
"The Environmental Kuznets Curve: Exploring a Fresh Specification,"
The B.E. Journal of Economic Analysis & Policy, De Gruyter, vol. 4(1), pages 1-28, June.
- David F. Bradford & Rebecca Schlieckert & Stephen H. Shore, 2000. "The Environmental Kuznets Curve: Exploring A Fresh Specification," NBER Working Papers 8001, National Bureau of Economic Research, Inc.
- David Bradford & Rebecca Schlieckert & Stephen H. Shore, 2000. "The Environmental Kuznets Curve: Exploring a Fresh Specification," CESifo Working Paper Series 367, CESifo.
- List, John A. & Gallet, Craig A., 1999.
"The environmental Kuznets curve: does one size fit all?,"
Ecological Economics, Elsevier, vol. 31(3), pages 409-423, December.
- Craig Gallet & John List, 1999. "The environmental Kuznets curve: does one size fit all," Natural Field Experiments 00527, The Field Experiments Website.
- Pesaran, H. Hashem & Shin, Yongcheol, 1998.
"Generalized impulse response analysis in linear multivariate models,"
Economics Letters, Elsevier, vol. 58(1), pages 17-29, January.
- Pesaran, M. H. & Shin, Y., 1997. "Generalised Impulse Response Analysis in Linear Multivariate Models," Cambridge Working Papers in Economics 9710, Faculty of Economics, University of Cambridge.
- Greening, Lorna A. & Davis, William B. & Schipper, Lee, 1998. "Decomposition of aggregate carbon intensity for the manufacturing sector: comparison of declining trends from 10 OECD countries for the period 1971-1991," Energy Economics, Elsevier, vol. 20(1), pages 43-65, February.
- Osman Zaim & Fatma Taskin, 2000. "A Kuznets Curve in Environmental Efficiency: An Application on OECD Countries," Environmental & Resource Economics, Springer;European Association of Environmental and Resource Economists, vol. 17(1), pages 21-36, September.
- Lise, Wietze, 2006. "Decomposition of CO2 emissions over 1980-2003 in Turkey," Energy Policy, Elsevier, vol. 34(14), pages 1841-1852, September.
- Friedl, Birgit & Getzner, Michael, 2003. "Determinants of CO2 emissions in a small open economy," Ecological Economics, Elsevier, vol. 45(1), pages 133-148, April.
- Jeffrey A. Frankel & Andrew K. Rose, 2005.
"Is Trade Good or Bad for the Environment? Sorting Out the Causality,"
The Review of Economics and Statistics, MIT Press, vol. 87(1), pages 85-91, February.
- Jeffrey A. Frankel & Andrew K. Rose, 2002. "Is Trade Good or Bad for the Environment? Sorting Out the Causality," NBER Working Papers 9201, National Bureau of Economic Research, Inc.
- Frankel, Jeffrey & Rose, Andrew K., 2003. "Is Trade Good or Bad for the Environment? Sorting Out the Causality," Working Paper Series rwp03-038, Harvard University, John F. Kennedy School of Government.
- Robert J. Hill & Elisabetta Magnani, 2002. "An Exploration of the Conceptual and Empirical Basis of the Environmental Kuznets Curve," Australian Economic Papers, Wiley Blackwell, vol. 41(2), pages 239-254, June.
- Richmond, Amy K. & Kaufmann, Robert K., 2006. "Is there a turning point in the relationship between income and energy use and/or carbon emissions?," Ecological Economics, Elsevier, vol. 56(2), pages 176-189, February.
- Stern, David I., 2000.
"A multivariate cointegration analysis of the role of energy in the US macroeconomy,"
Energy Economics, Elsevier, vol. 22(2), pages 267-283, April.
- David I. Stern, 1998. "A multivariate cointegration analysis of the role of energy in the U.S. macroeconomy," Working Papers in Ecological Economics 9803, Australian National University, Centre for Resource and Environmental Studies, Ecological Economics Program.
- Bulte, Erwin H. & van Soest, Daan P., 2001. "Environmental degradation in developing countries: households and the (reverse) Environmental Kuznets Curve," Journal of Development Economics, Elsevier, vol. 65(1), pages 225-235, June.
- Torras, Mariano & Boyce, James K., 1998. "Income, inequality, and pollution: a reassessment of the environmental Kuznets Curve," Ecological Economics, Elsevier, vol. 25(2), pages 147-160, May.
- Coondoo, Dipankor & Dinda, Soumyananda, 2002. "Causality between income and emission: a country group-specific econometric analysis," Ecological Economics, Elsevier, vol. 40(3), pages 351-367, March.
- Heerink, Nico & Mulatu, Abay & Bulte, Erwin, 2001. "Income inequality and the environment: aggregation bias in environmental Kuznets curves," Ecological Economics, Elsevier, vol. 38(3), pages 359-367, September.
- Hamilton, Clive & Turton, Hal, 2002. "Determinants of emissions growth in OECD countries," Energy Policy, Elsevier, vol. 30(1), pages 63-71, January.
- Roger Perman & David I. Stern, 2003.
"Evidence from panel unit root and cointegration tests that the Environmental Kuznets Curve does not exist,"
Australian Journal of Agricultural and Resource Economics, Australian Agricultural and Resource Economics Society, vol. 47(3), pages 325-347, September.
- Perman, Roger & Stern, David I., 2003. "Evidence from panel unit root and cointegration tests that the Environmental Kuznets Curve does not exist," Australian Journal of Agricultural and Resource Economics, Australian Agricultural and Resource Economics Society, vol. 47(3), pages 1-23, September.
- Dinda, Soumyananda, 2004. "Environmental Kuznets Curve Hypothesis: A Survey," Ecological Economics, Elsevier, vol. 49(4), pages 431-455, August.
- Shafik, Nemat, 1994. "Economic Development and Environmental Quality: An Econometric Analysis," Oxford Economic Papers, Oxford University Press, vol. 46(0), pages 757-773, Supplemen.
- Canas, Angela & Ferrao, Paulo & Conceicao, Pedro, 2003. "A new environmental Kuznets curve? Relationship between direct material input and income per capita: evidence from industrialised countries," Ecological Economics, Elsevier, vol. 46(2), pages 217-229, September.
- Shafik, Nemat & Bandyopadhyay, Sushenjit, 1992. "Economic growth and environmental quality : time series and cross-country evidence," Policy Research Working Paper Series 904, The World Bank.
- Roca, Jordi & Alcantara, Vicent, 2001. "Energy intensity, CO2 emissions and the environmental Kuznets curve. The Spanish case," Energy Policy, Elsevier, vol. 29(7), pages 553-556, June.
- Koop, Gary & Tole, Lise, 1999. "Is there an environmental Kuznets curve for deforestation?," Journal of Development Economics, Elsevier, vol. 58(1), pages 231-244, February.
- de Bruyn, S. M. & Opschoor, J. B., 1997. "Developments in the throughput-income relationship: theoretical and empirical observations," Ecological Economics, Elsevier, vol. 20(3), pages 255-268, March.
- Moomaw, William R. & Unruh, Gregory C., 1997. "Are environmental Kuznets curves misleading us? The case of CO2 emissions," Environment and Development Economics, Cambridge University Press, vol. 2(4), pages 451-463, November.
- Schipper, Lee & Ting, Michael & Khrushch, Marta & Golove, William, 1997. "The evolution of carbon dioxide emissions from energy use in industrialized countries: an end-use analysis," Energy Policy, Elsevier, vol. 25(7-9), pages 651-672.
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