Evaluating Efficiency of Rock Blasting Using Data-Envelopment Analysis

The prime objective of this paper is to demonstrate how a public roads authority charged with reviewing the performances of its agencies can analyze the efficiency with which services are produced. Specifically, we show, within the framework of a deterministic nonparameteric data- envelopment analysis (DEA), how the Norwegian Public Roads Administration is able to assess the performances of its rock-blasting agencies or units and target areas for improvement. A DEA model with variable returns to scale is applied to establish boundaries of the best practice. The study indicates substantial variation in efficiency scores across units. The rock-blasting sector’s input-saving potential is found to be in the range of 46–55%, while the output-increasing potential ranges from 89 to 150%. There is a significant correlation between size and efficiency scores indicating that larger units perform better than smaller ones. Precautionary blasting, mainly performed in densely populated areas and units, costs per volume of rock blasted explain much of the variations in efficiency scores. Any policy implication should, therefore, carefully examine exogenous factors.