Data envelopment analysis (DEA) is commonly employed to evaluate the efficiency performance of a decision making unit (DMU) that transforms exogenous inputs into final outputs. In such a black-box DEA approach, details of an internal production process of the DMU are typically ignored and hence...

Assessing the changes over time in the efficiency of firms participating in competitive markets has always been a major concern to researchers and experts alike. With respect to the US wireline telecommunications sector, recent changes in unbundling regulations, as well as intermodal competition...