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 nonparametric data- envelopment analysis (DEA), how the Norwegian Public Roads Administrat ion is able to assess the performances of its rock-blasting agencies o r units and target areas for improvement. A DEA model with variable re turns to scale is applied to establish boundaries of the best practice . The study indicates substantial variation in efficiency scores acros s units. The rock-blasting sector's input-saving potential is found to be in the range of 46-55%, while the output-increasing potential rang es from 89 to 150%. There is a significant correlation between size an d efficiency scores indicating that larger units perform better than s maller ones. Precautionary blasting, mainly performed in densely popul ated areas and unit costs per volume of rock blasted explain much of t he variations in efficiency scores. Any policy implication should, the refore, carefully examine exogenous factors.