Metafrontier slack-based nonparametric technologies with convex and nonconvex measurement of directional distance functions: empirical exploration of high-tech industries

High-tech industries make an essential contribution to improving innovation ability and promoting industrial structure optimisation. It is essential to examine the development level and regional differences within China's high-tech industry to enhance the quality of economic development. This paper develops a metafrontier slack-based nonparametric method of the directional distance function to perform an efficiency analysis. Distinguishing the development differences of regional high-tech industries and identifying the main causes of inefficiency sources. We are the first to combine convex and nonconvex technologies to calculate group and meta frontier efficiencies, and the technical gap ratio for the high-tech industries. Empirical results indicate that the nonconvex method can provide more reasonable explanations for green innovation efficiency.