This paper provides an empirical demonstration for a practical approach of efficiency evaluation against the background of limited data availability in some regulated industries. Here, traditional DEA may result in a lack of discriminatory power when high numbers of variables but only limited...

This paper considers the question of whether changes in persistence have occurred during the long-run evolution of U.S. prices of the non-renewable energy resources crude oil, natural gas and bituminous coal. Our main contribution is to allow for a structural break when testing for a break in...